Converters?

Hi, I'm fairly new to RollerCoaster simulators. I know that you can ride RCT1 coasters in NL, but is there any way to convert the remaining dozen or so types of files so you can ride them in NL? Because it seems NL is the only rollercoaster simulator for Mac.
I appreciate everyone's help. [|)]

Nope, just RCT1...

Yep, nothing but RCT1. Generally, RCT tracks are absolute crap in NL, and will prove to be very, umm, forceful [:)]

Yeah, I expected as much. :-/
*sigh*

yeah Ive imported some rct1 coasters that just valley out right at the beginning. It's a near useless feature.