I just intalled the 100c version for my SX530. I got it all working but it seems the raw images are completely blued out and you can see the radius of the lens around them. Is this normal?
The lens vignetting and distortion is normal, that's what the camera actually sees. The camera corrects this in software for the jpeg, and you can do the same with appropriate settings or lens profile in a raw conversion program.
The color may or may not be a bug.
Are you using DNG or CHDK raw?
What software are you using to view it?
Can you upload the actual raw image somewhere (too large for forum attachmetns, use google drive, dropbox etc)?