Normally, the magic plugin doesn't get updated with new sets, until the card images start to appear on Gatherer. That said, there are certain cards for Worldwake that have been officially spoiled, and had their image released, that I'd really like to test with. Is there anything I could do to help update the plugin with the currently spoiled cards, so that we can test a bit before the official, big update?
This topic already exists. Long story short: Yes, you can, but it would not be updating the actual Magic plugin, which is updated by a user called Bort. If you make the edits, it will essentially create two separate plugins, which can occasionally lead to warnings and errors within Lackey. Basically, if you want to do it for yourself, it's fairly easy to implement. If you want to share it or take it online, it's kinda more trouble than it's worth. You can always just proxy the cards.
I just recommend using Mox Sapphire as a proxy for Jace...