We are aware that the Linux client crashes many times while trying to upload Linux games. It is on the list of bugs to be fixed in the client now that the client has been released. We are hoping that it will be fixed soon so that an official version of the client can be released soon. You can track the process of this bug report by going here:
Github.com
UPDATE:
This has been fixed in the open source version. There are other fixes as well for the Linux client. I recommend you download and compile the Linux client yourself.
How to fix this ?
This has been fixed in the open source version of the client. I would recommend you go and download the source code and compile it yourself.