I'm guessing, but are these made with custom profiles?
You could try exporting them by IFC, which can be a bit iffy as well with custom profiles, but usually a little playing with the direction you drew the wall or beam with the custom profile solves the problem.
Erika
Architect, Consultant
MacBook Pro Retina, 15-inch Yosemite 2.8 GHz Intel Core i7 16 GB 1600 MHz DDR3
Mac OSX 10.11.1
AC5-18
Onuma System
"Implementing Successful Building Information Modeling"