Doom Builder Macro Conversion?

Basically, I'm converting a load of all maps I made to run with my new GZDoom Resource; but this means I first have to change the map format (not too much of a problem) but I also have to replace every texture and every Thing... so, if there was a way to save a small script or something that could replace any texture or flat with a new texture or flat and any thing number with another so that I could convert my maps things and textures by simply running a script?
Basically a find and replace macro? Maybe support for changing line actions too -but that probably wouldn't work so well for me due to the second format using parameters.

Use zwadconv to convert map formats

Needs WadC

Nope, these programs don't do the job...
I need a way to script a series of find and replace commands in Doom Builder, which can be saved and reused on other maps.