i've been keen for all data in the text files (aiw,tdf,gbd) to be entered and stored in btb. hopefully it will be there if he gets to v1. it sounds like he has gotten himself busy, so that might be a while. so i'll wait for aiw in v0.8
the good news is you can select which of the tdf materials have which properties (roada, rdax, rged, gras etc) within btb materials right now. then if you want custom values, type up your data and make a copy for the btb /support folder. that will set them for all your tracks though, so back up the orig.
but yeah, dirty lines and such sounds like fun.