Well, I'm not a lawyer by any means, but if my understanding is correct even though Runequest is itself a copyrighted work, creating a Savage Worlds version of it would be a derivative work and should fall under fair use. However, if you did copy out of other works in making that the verbiage from whatever other sources you used could themselves be copyrighted, which could present a problem for you. Ensuring you are not using the exact language of any other source, even if you are using some of the ideas, might cover you there (but it might not, I can't really say for sure beyond my limited understanding of copyright law).
When you mention "submitting", though, do you mean sending it to Lone Wolf to include as an official setting in the updater for Hero Lab? If so you might need to directly PM someone with the company to discuss that. At a guess I'd think they are primarily interested in offering up published works, and even then they'd need to have some agreements in place with the publisher to be able to offer the data file up in an official format like that as well, I believe. I know they have something like that in place with Pinnacle for all of those settings, and I believe they've done the same with StoryWeaver for the High Space data file they offer that JBear did. I've heard rumors that some of the other publishers are less keen on doing anything like that, especially with a free data file. I don't know for certain their reasons but it may have to do with feeling as if the kinds of things in the data files are somehow the meat, so to speak, of their setting. Personally I've known plenty of folks who've seen a data file and though those Edges/Hindrances and such were all interesting enough to whet their appetite for actually buying those products to get all the really good background details that aren't in a data file, but that's just my guess.
In any case I think the unwritten rule here is that most fan made files could be offered between fans, in no different a way as people share their settings on Savagepedia, for example, but if there might be any potential legal issues I think Long Wolf probably doesn't want to be involved. You can always try to contact maybe Liz, though, and see what they have to say about it.
