Dialog button action woes

[mad rabbit 0]

I have been dissecting a CTI map to learn about scripting and am having trouble with a dialog button I created and its relevant action.

For those familiar to CTI maps:

I wish to create 2 seperate vehicles from the Control Center with 2 seperate buttons that appear after a certain upgrade. The buttons all appear and the upgrade disappears according to plan (thanks to previous reply by "Spinor") however the desired function of the button does not work and I get the following error:

<table border="0" align="center" width="95%" cellpadding="0" cellspacing="0"><tr><td>Code Sample </td></tr><tr><td id="CODE">

[_side,_factories Select _currentFactoryType,|#|M101WestType,noScript,GrpNull,false] Exec "main\BuyVehicle.sqs"

I have modelled the button on the create "Independent Salvager" button from the repair menu, and the button seems to be accessing the right script (BuyVehicle.sqs) but the execution halts.

From what I understand this is either due to:

1) An error in my unit description/listing in the main\Stats.sqs

which may have occured due to the listing of the upgrade enabling the buttons as one entity and the listing of two units/vehicles as a result of that upgrade. I may have got muddled up but I have checked it through as best I could....

OR

2)The fact that the control center is not a valid factory.

consequently the Independent Salvager button has an entry in the GUI\UpdateGUIFactoryMenu.sqs that I mimicked for the 2 vehicles I wish to create with the 2 buttons in the control center dialog).

I am unsure of what to post in terms of code to be analyzed so for all you CTI map making gurus out there, please let me know what to post to help my explaination.

Thanks in advance.