Let me guide you through some of the tools, so that you can investigate some of that yourself.
In the develop menu, make sure that "Enable Data File Debugging" is checked.
Again in the Develop menu, choose Floating Info Windows, then Show Hero Fields.
That will pop up a list of all the field values that are stored on the hero - look through that for encumbrance-related things (these happen to be very close to the top of the list, but the next thing you're looking for may be further down).
Now, add various armors, equip and un-equip them in various combinations, and watch these values on the hero change - figure out which of those values is doing what.
Next, we'll figure out when those are calculated. Go back to floating info windows, and choose Show Selection Tasks. Scroll down that list to an item called "Hero (actor)", check that item, and say OK.
Look through that list for encumbrance-related things - you'll see that the maximum is calculated at Traits/6100, and the penalty is calculated at Traits/6200. So, what you'll want to do is change the maximum from Body + Body to Strength + Body. You can do that by subtracting Body and adding Strength. Since the current value is calculated at Traits/6100, and that value is used at Traits/6200 to calculate the penalty, you'll want to make your change between those two times. Traits/6150 should be good.
Okay, the best way to do this is with an item called a Mechanic, but I haven't had the time to add that tab to the editor yet, I'm sorry to say.
So, open the editor, create and save a new file, and then close the editor. Now, open a text editor program or XML editor (like Notepad) (not a word processor - those may try to add special coding to the file that might interfere with HL's use of it).
Look for:
Code:
<document signature="Hero Lab Structure">
and
Between the ">" of document signature and the "<" of /document, paste the following:
Code:
<thing
id="mechPaxCmp"
name="_Pax_'s Campaign House Rules"
compset="Mechanics">
<usesource source="PaxCamp" parent="UserParent" name="_Pax_'s Campaign"/>
<eval index="1" phase="Traits" priority="6150">
<before name="Calc Encumbrance Penalty"/><![CDATA[
herofield[acEncumMax].value -= #trait[attrBod]
herofield[acEncumMax].value += #trait[attrStr]
]]></eval>
</thing>
You can change what's in the id="", just keep that to 10 characters or less with no spaces. You can change the name="". In the <usesource line, you can also change the source="" (same rules as id="") and name="".
Once you've pasted that in, save and close the text editor, and go back to Hero Lab. In the Develop menu, choose "Quick Reload Data Files"
Now, go to the configure hero form (ctrl-k), and at the top, you'll see "_Pax_'s Campaign" (or whatever you changed the name of the usesource line to). While that's checked, this mechanic will be used, and it will apply this house rule. You'll probably want to change the default settings, and then open any other characters that need this and change their settings, too.
The file you created can be emailed to the rest of your play group - they'll put it in the same location, and then they'll have access to this, too.
If you have any trouble with that, please tell me.