Ging1:
Based on a quick look at one of the cabinets in ArchiCAD 15 (Cabinet Base 1D 15), this value (0.02) is hard coded into a macro used for the cabinet body. So there is no way to change this value parametrically, you would need to use GDL to alter the value in the macro, which could lead to other problems with any object that also uses this macro (fa_gen_basecabinet). Short answer: not easily.
You should add a Signature to your Profile (click the Profile button near the top of this page) with your ArchiCAD version and operating system (see mine for an example) for more accurate help in this forum.
David
