This is embarrassing. I was going to make a release with the new features discussed below this weekend, after more testing. But I just discovered a bug in my installer setup that didn't show itself on my dev machine (a missing dependency that I had on my dev machine because it's my dev machine). While this is alpha software, I feel pretty stupid having pushed out an MSI that didn't actually work, especially since I did at least do nominal dev testing on a second machine.
I've just put up a new build, sooner than expected, with the fix and the new features. I also put up the dev and release builds. The only difference is that the dev build will show asserts and exceptions and logs data (which elements were blocked or not blocked) to %TEMP%\Low\adblock.log. If you're interested in this sort of thing, try the dev build. If not, stick with the release.
(In the future, I'll provide a simpler way for getting those data, but I didn't want to hold this release up any longer due to the MSI bug.)
As always, thanks for your patience while I'm still in the apha stage, and use the Discussions page to let me know about any problems.