After inserting a model in cga using i(), you can rotate it around it's scope's center using r() and specifying the centerSelector as scopeCenter.
r operation—CGA | ArcGIS
To rotate and scale, you could translate, rotate and scale about the origin, and then translate back. Translate using relative offsets.
Lot -->
i(asset, yUp, keepSizeAndPosition)
Transform(assetInfo(asset,tx)/scope.sx, assetInfo(asset,tz)/scope.sz)
Transform(relOffset_x, relOffset_z) -->
t('-relOffset_x, 0, '-relOffset_z)
r(0, 90, 0)
s('2, '1, '0.5)
t('relOffset_x, 0, 'relOffset_z)