Converting A Sketchup 2018 file to Sketchup 2015 without using 3D Warehouse

Hello,
Is there any way of converting a Sketchup 2018 Model to a 2015 model without goign through 3D warehouse?
Just wondering because I cannot get onto it because of internet filters.
Thanks

Eneroth3 has an extension that can let you open newer files in an older version. It’s in the Extension Warehouse. See: https://extensions.sketchup.com/en/content/eneroth-open-newer-version

Has anyone come across similar something to accomplish this for Mac OSX?

No.

What version of SketchUp are you using? If it’s 2016 or older, your best option is to download the Collada file and import that.

Please complete your profile.

Dang. I’m using SketchUp 2015.

Thanks for the info.

/bds.