Expert Advisor

 Why does the Expert Advisor generate an entry signal, but the corresponding Exploration does not?
Assuming that the same dates/same number of records are loaded, The Exploration could have an additional layer of filtering criteria designed to eliminate securities with an unacceptable criteria. For this reason, the Experts should only be attached to securities generated by running the Exploration.

 Why do some Expert Advisors not have signals in the same place as their corresponding system tests?
Without seeing exactly how both your System Test and Expert are constructed it is impossible to answer this completely; however, there is one general statement we can make that may help you understand. These two features share some aspects, but are not designed to exactly duplicate each other. The System Tester is used to test a mechanical system for profitability, whereas the Expert Advisor is used to alert you of conditions in the price data that present opportunities - conditions that your knowledge and experience have shown are good times to make a move. You may respond by buying, selling, or simply watching the security’s activity more closely. You may have gained this knowledge through testing your successful System, so the Expert may use the same formulas, but the two features don’t behave quite the same way.
The System Tester will act on conditions it sees and simulate a reaction, the Expert Advisor cannot. For instance, the System Tester might see a condition that the formula in Buy Long has defined, and initiate a simulated purchase; however, although the Expert Advisor can been shown how to look for the same condition by using the same formula, the Expert cannot execute a purchase - only you can. The Expert may advise you to buy, by putting up a symbol or alert, but you must decide whether to act on that signal.
The Expert Advisor is never aware of when you buy or sell - it only alerts you to price conditions. It could put up more symbols than the System Tester would; for instance, the Expert could put up one Buy arrow, then a week later put up another - two Buy signals "back to back", i.e., without any intervening Exit or Sell.
The System Tester should never do this because it "knows" to Close Long only if the current position is Long, and to Close Short only when the current position is Short.
For the Performance Systems, the assumptions require the following settings:

Open the Enhanced System Tester and edit the test in question.
Make sure the Buy order, Sell order, Sell Short order, and Buy to Cover orders use no strategic delays.
Click the Stops tab and make sure all the stops are disabled.
Close the test and click New Simulation.
Select the test
Click Next
Select the security to test.
Click Next
Select points only tests, in the System Testing Options dialog.
Then click on the Advanced button.
Click the Trade Execution tab and uncheck Realistic Market Prices. Set all price fields to Close and set the trade delay to 0.
Click Okay
Click Start to run the test.

 How do I enter a custom formula into the Expert Advisor?
 MetaStock 11 - Current

There are up to five different ways to be notified when using an expert advisor to show that a condition has been triggered. These include a trend ribbon, commentary window, bar highlight, symbol, and alert. Creating these five items in a custom expert advisor are reviewed below.

Open MetaStock.
From the Tools menu on the main toolbar, select Expert Advisor.
Select New from the right-hand menu to open Expert Editor.
In the Name tab, name the custom expert advisor, and provide notes about the expert if desired.
How do I create a Trend Ribbon for a custom Expert Advisor?

Click the Trends tab.
Paste the custom formula for the bullish trend in the Bullish window.
Paste the custom formula for the bearish trend in the Bearish window.
Select the Ribbon button, and select the display options for the bullish and bearish trends on the chart.
If the custom expert will only contain a trend ribbon, click Ok create the Expert Advisor, and close the editor.
How do I create Highlights for a custom Expert Advisor?

Click the Highlights tab.
Select New from the menu on the right hand side, this will open the Experts Highlights Editor.
Type the desired name
Select the desired Color.
Insert\paste the formula in the Condition window.
Click OK to close the highlight editor
Repeat the above process to create multiple highlights.
If the custom expert will only contain bar highlights, click Ok to create the Expert Advisor and close the editor.
How do I create Symbols for a custom Expert Advisor?

Click the Symbols tab.
Select New from the menu on the right to open the Experts Symbol Editor.
Type the desired name.
Insert\paste the formula in the Condition window.
Click the Graphics tab.
Select the symbol to be used from the Graphic list.
Select the Size for the symbol.
Choose the Color for the symbol.
Type in a Label if one is desired to be displayed on the chart for the symbol.
Select the Symbol Position and Label Position.
The label font, color, and size are controlled by clicking the Font button. The gray box to the right shows how the symbol will appear when it is added to a chart.
Click OK to close the Expert Symbol Editor.
Repeat the same process to create multiple symbols.
If the custom expert will only contain symbols, click Ok to create the Expert Advisor and close the editor.
How do I create Alerts for a custom Expert Advisor?

Click the Alert tab.
Select New from the right-hand menu to open the Expert Alert Editor.
Type the desired name.
Insert\paste the custom formula into the Condition window.
Select the Alert tab.
Type in the text that the alert is to display when it is triggered.
Click Ok to close the Expert Alert Editor.
Repeat the same process to create multiple alerts.
If the custom expert will only contain alerts, click Ok to create the Expert Advisor and close the editor.
How do I insert the text for an expert advisor commentary window?

Click the Commentary tab.
Within the commentary window, insert the desired text for the custom expert advisor.
Add any desired formatting, such as font size, font color, bold, and italics.
If the custom expert will only contain a commentary window, click Ok to create the Expert Advisor and close the editor.

 How can I auto-hide the Expert Commentary in MetaStock?
Starting in MetaStock 19, you can set the Expert Commentary to Auto Hide and have it fly-out when you want it. To Auto Hide the Expert Commentary, follow the steps below;

MetaStock v19 --> Current

Open MetaStock.
Open a chart.
Attach an Expert Advisor.
Open the View menu.
Select Expert Commentary.
Right-click on the title bar of the Commentary.
Select Auto Hide.

Or

Open MetaStock.
Open a chart.
Attach an Expert Advisor
Open the View menu.
Select Expert Commentary.
Drag the Expert Commentary to the far edge of the new Pane icon.
To turn this feature off, right-click on the Expert Commentary and select either Float or Dock

 I'm trying to create an expert advisor but the "new" icon is greyed out.?
In MetaStock versions 19 and 20, you will need to open a chart first before you can create a new Expert Advisor.