Let me put it to you a different way:
If I don't understand how to properly troubleshoot with your OS, then i can't rule out that it isn't a problem with your set up.
Every single Ubuntu/Linux user I have attempted to help has had a different version of Java, used a different directory, etc.
Right now, the "support team" is 95% me. Would you have preferred I send you to someone who might not even log in until next month?
We do it for free. We're volunteers. We have jobs, we go to school, we have families just like you. We aren't manning the desk 24/7. We don't have to help anyone at all. I cannot provide support for Linux users. I am the person who responds 95% of the time. I am not going to provide support to someone when I can't even rule out basic set up issues.
I spent several days looking at tickets that I didn't know how to answer. Over the course of that several days, I Googled the issues, checked the forums, and also noted that no one else had been on the desk answering tickets.
Edit: Also, the support we can offer for installing servers is in
this article. It redirects to the Minecraft Wiki. We have vanilla-styled servers, therefore all installation is exactly the same as a vanilla server. The only difference I've found is when you're adding RAM, and you need to use [Modpack]_Server.jar instead of Minecraft_Server.jar.
Edit, but not regarding your problem: The most "developer" we get presently is one person who is part of the modpack team. As far as I know, none of us are developers.
I would also suggest that some more support is added for Linux users as it's become more popular with FTB servers as they perform better on the OS. I could right some post for FAQ's for troubleshooting if people want something like that
I have openly asked for people's input for what could be added to the Knowledgebase in the past. It is ALWAYS welcome, because we don't know everything. We can't provide support for things when we don't know how.