Is there something I can do about this, or is it somekind of issue in the project?

I assume it's this computer we are talking about. As you can see in it's task list, it's generating nothing else than client errors so it's down to 1 task per day and core.

Well, it's project issue in combination with some computers, see this thread. The only thing you can do now is moving it to another BOINC project untill they find and solve the issue.

The existence of such a firewall implies your employer does not wish for their machine to be used in this way. Or at least that they want the opportunity to formally approve such a use.

All of the download servers are controlled by BakerLab and all use a common file system to ensure they are distributing identical copies of things. If a download server had a problem of some king there would be many people getting signature errors at the same time. I have not seen reports that would bolster that theory.

Which AV are you using?

Sometimes anti-virus software or firewalls will modify the executable. You may have to add Rosetta to a list of websites or directory names not to be scanning.