Uh oh! There was an error submitting the form: validation.mimetypes

Does anyone know what this means? I've been away for a while and in the mean time the submission process was updated (yay!) maybe one of my files is off, it's been a LONG time since I submitted a CW, and I've never submitted one of my own, always been a commissioned one, so it's probably a fault on my end. help is appreciated!

I do not think it's your end. Seems a lot of people are having issues with the CW features right now.

https://subeta.net/forums.php/read/921097/Unable-to-submit-new-CW

validation.mimetypes usually happens when an image is not in the correct file type. Custom Items must be in .GIF and Custom Overlays must be in .PNG

Thanks both of you!