No hands on experience, but what I've heard is that Modo isn't that great with high polygon models.
BIM models generally are very detailed.
You can install the Polycount goodie for your ArchiCAD to see which part of your model is poly heavy and see if you can leave it out of export or reduce the polycount in someway (some objects have low quality settings).
'Sloppy' modelling can also cause quite high poly counts. For example: a complex profile wall with tiny holes or lots of nodes on a shape that is just a rectangle. You will get a lot of extra surfaces this way.
Erwin Edel, Project Lead, Leloup Architecten
www.leloup.nlArchiCAD 9-26NED FULL
Windows 10 Pro
Adobe Design Premium CS5