Subsite Theme - upload image default location


I'm having a small issue with a vCard theme called Zwin. I already tried to contact the theme developer, but it seems he left his project. Because its a small issue and besides that the theme is really the best choice at this moment, I was hoping somebody here could help me.

That being said, this is the problem I'm having: The theme is being used on a multisite, where subsite owners can change the Theme profile image (used on the homepage). There is where the problem begins, because the image is being saved as a default name inside the theme's folder, it will change on everyone's subsite! The last person who changes their profile image, thats is what every subsite will get.

I was thinking if I could change a code inside the Theme that would not upload the image inside the Theme's folder but on the subsite owners own upload folder. Like avatars. That would solve the problem. Unless somebody has a better suggestion or easier solution.

Sorry for the long text. I hope this all makes sense and somebody can tell me what to do to fix this without to go to the job hiring section. Cause there is no budget atm.

Mucho thanks in advance!