AutoCAD Inventor :: ILogic / Use Same Variable In Multiple Subs / Functions?

I have an iLogic rule in which I'm trying to set three user parameters for the gage of each leg of a steel angle. I want Inventor to set the gage based on the length of each leg. Here's the table I referenced for gages: [URL].

In my code, I have a sub called DetermineGage which takes the leg length, whether it's the short leg or the long leg, and determines the gages that should belong to that leg. Inside of that sub it calls on a sub called ApplyGage which then applies the determined gage to the rule's gage variables. The main sub then grabs those variables and applies those values to the actual user parameters.... In theory.

The rule executes ok with no errors, but doesn't change the value of the user parameters; they're always "0". As best I can tell, the "oGage" variables I used in the rule don't even get assigned the correct value, which makes me think the DetermineGage and ApplyGage subs can't even access the oLegLength or oGage parameters to read or set them. I don't want to use global parameters because I've heard that can make programs very unstable over time and is just bad practice. How can I make these variables accessible to all subs IN THIS RULE, no more no less?
 
Sub Main()Dim oLegShort As Double = Min(G_W,G_H)Dim oLegLong As Double = Max(G_W,G_H)Dim oLegLength As DoubleDim oGage As DoubleDim oGage1 As DoubleDim oGage2 As Double'Short Leg:oLegLength = oLegShort'Call DetermineGages sub to set oGage variables:DetermineGages()On Error Resume Next'If gage parameter does not equal true gage, set it equal:If Parameter("ShortLegGage") <> oGage ThenParameter("ShortLegGage") = oGageEnd If'Assume error means gage parameter does not exits. Create and set equal to true gage:If Err.Number <> 0

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