After fixing the bug regarding going onwards and backwards, and errors were not showing properly (when the instance had errors), now another bug has been fixed.
When uploading an instance, and in the same step, the instance was changed, the errors from the instance that didn't comply with the schema, weren't being saved. That was fixed.
Also, the button was not disabled when there were errors in the instance. This was also fixed.
After fixing the bug regarding going onwards and backwards, and errors were not showing properly (when the instance had errors), now another bug has been fixed. When uploading an instance, and in the same step, the instance was changed, the errors from the instance that didn't comply with the schema, weren't being saved. That was fixed. Also, the button was not disabled when there were errors in the instance. This was also fixed.