I just started adding some traditional charters and have hit a problem. Some come up with variants like the ones below.

个 - 個 or 箇 - - - 为 - 為 or 爲

说 - 說 or 説 - - - 里 - 裡 or 裏

The differences aren't big, so reading shouldn't be a problem， but how do you know which one to learn to write? Is there a standard, and if so where can I check, or is one from Hong Kong and the other Taiwan?

箇　and 説 are Japanese Kanji

為 and 爲 both show up , but 為 a bit more frequently

裡 and 裏 both show up. No difference in meaning or usage

Nothing to do with HK or Taiwan

A lot of the time, especially if they are very similar, then you should pick the first one in the Skritter list. Unless the first one is the same as the simplified, in which case that might just be a radical form.

Then there are ones where the two variants are different, and you should get both. Hard to tell sometimes!

I would recommend you look up the simplified character on mdbg.net (you can easily do that through the skritter details pop-up).
This dictionary generally does a good job showing where there is no difference or meaning or usage and when there is:

e.g.
http://www.mdbg.net/chindict/chindict.php?page=worddict&wdrst=0&wdqb=%E9%87%8C+
http://www.mdbg.net/chindict/chindict.php?page=worddict&wdrst=0&wdqb=%E5%8F%91

but apparently, you can't link to search results... :P

just look up 里 and 发 to see how it deals with traditional variants.