Amiga C - GUI Question

[Kernel]

I have a very noob question as far as Amiga C programming goes so my apologies ahead of time...

I have the source to an old program want to play with.  The workbench window mode of it appears corrupted under 3.1 in the sense that the size is not standard and it's not picking up Birdie or VisualPrefs settings like other windows do.

Question is, would a simple compile using the 3.9 dev kit correct this or is this possibly some custom code that defined window border sizes etc. custom to the program?

I'm not looking for a real in depth answer, just more of a "yep, a recompile should fix that" or a "nope, this stuff is typically defined in code so dig in!", though I don't mind if it blows up into more of a discussion.

Thanks.

[Kernel]

@Pat the Cat:

They are talking about leaving the OS turned on and just doing custom drawing of titlebars, etc.

Yes I believe this is what I'm looking at... it's an old BBS program I used many years ago and thought it would be a good place to play around since it's freeware.  It can either open on its own screen or in a WB Window, it just that like I said on 3.1 it doesn't appear to be style compliant and I'd like to take a shot at changing that first.

Thanks all!