It's easier to install a proper version of Linux onto a Chromebook than to port SRB2 to ChromeOS. So easy anyone can do it.
1. Use this
tutorial guide to install a proper Linux desktop in a chroot using Crouton. For the "-t" option, I suggest lxde if it's a valid option. If not, xfce will do the job. I cannot possibly recommend Unity on a chromebook; if you choose to install it, it will eat your framerate.
2. Download SRB2's installer executable from the main page, open it with the archive manager, extract the game data to a new folder, and download and extract the patch to the same folder.
3. Download the Linux executable for the latest version of SRB2 from
here. Use Linux/Release/lsdlsrb2 for 32-bit and Linux64/amd64/Release/lsdlsrb2 for 64-bit. Use LInux/armel/Release/lsdlsrb2 for ARM.
4. [May not be necessary] Right click on lsdlsrb2 from the file manager, select Properties. In the permissions section of the dialog, ensure that you are allowed to execute it. Once this is done, you should be able to double-click lsdlsrb2 and have it run.
If there's a hangup at any step in this guide, post here and I'll get right back to you, no matter how stupid of a question you may think you have. Just keep in mind that I do not own a chromebook and have not tested this guide; yet at the same time I have no reason not to trust this guide.
EDIT: Removed the incorrect anti-arm content.