Opening CATIA V5 R20 files in R18 help!

Hi guys! New poster here, so I'm sorry if I'm in the wrong section/breaking the rules here. I'm hoping someone can help me out, I've been working on a project for a job interview, and I've just realised that the version of CATIA I've been making it in at work (R20) is different to the one I've got at home (R18), so I now can't open the files I've made to render them all nice and prettily.

Is there any easy free-to-use conversion software out there that'll make my R20 files work in R18, or am I basically scuppered?

If there's anyone out there running CATIA V5 R20 who'd be willing to convert a couple of files into iges for me then I'd be massively appreciative. Really need to do well in this interview...

First, try to save as a step file then open in the version you want

Second, try the following

Click on Tools->Utility
Double click on "downward compatibility"
Click "member"- select the file to convert
At the top select the version to which you want to convert the file- set the target folder- click "run"

Thanks for the quick response, Kelly! I've never noticed that Downward Compatibility utility before. Will need to remember that for future reference! Looks like that would work for ensuring future projects I'm working on at the office will work on my system at home (which is certainly good to know!), but it doesn't seem to let me open the files up at the moment :(