building info.cas files

[Makanyane]

I've managed finally to get a new model to appear on battle map using custom tiles, initially and embarrassingly you could walk through it! I've managed to stop that by assigning an existing info file to it in descr_building_battle.txt eg:

statue_meta
{
full_health 10
localised_name ambient
level
{
min_health 0
battle_stats
item statue_meta
physical_info info_construction_48x32.cas
}
}

but suspect that probably isn't really the right info for the new model and that artillery shells may go sailing through it at some point!

info_construction....cas don't seem to exist but there is similar file in the RTW packs \DATA\MODELS_BUILDING\INFO\INFO_CONSTRUCTION_48X32.BPI

does anyone have any idea how a new info file could be made and installed - or even if you can view the bpi files to work out what height they go to?