Hello.
If you are facing any technical issue like this, please send us an e-mail to support@kentico.com. This FAQ article deals only with specific issue about web parts. If you think your issue has the same pattern, please make sure that all your files within /CMSVirtualFiles/WebPartLayouts folder are included into a project before its deployment. Otherwise, please send us an e-mail to e-mail address above, or open new topic in Questions & Answers section on our Devnet. Thank you.
Best Regards,
Radek Macalik