Everything has been solved, you can safely upload images once again.
Let me know if there any other problems.

We are having some problems with the server right now, and apparently, the upload system is not working correctly.
This is not a problem with the site, but with the hosting server, that apparently is having memory issues.
When you try to upload an image, the GD library needs to make some transformations to the image to create the thumbnail and the reduced images.
During this process, a quite a bit of memory is required and it is in that moment when the server is failing and giving a memory allocation error.
I have contacted the server's support team to see what the problem may be.

If anyone of you received an error similar to this one: Allowed memory size of 8388608 bytes exhausted (tried to allocate 5600 bytes) you will need to re-upload your images when the problems are resolved...

I've done some testing and it appears that this problems does not happen with images 1024x768 or smaller, so you should able to upload those without problems. Let me know if you find any other issues.

Sorry for the incovenience...