I just released wpSearch 18.104.22.168 about 5 minutes ago, and the memory issue should be addressed. So far, one wpSearch user has had their memory issue fixed with the update.
Thanks for bringing this up, ririzaryy.
To rschilt, the indexing page definately needs a status bar, but in light of the last major bug, it had to take a back seat. The page hangs because your index is building, which can take a long time depending on the number of posts / comments in your blog.
The last benchmarking of wpSearch resulted in a full index build of 6,000 light posts in about 45 minutes. This is a necessary part of wpSearch (if we were using Java, and not PHP, it would be done in a minute or two).
Once this process is over, is unlikely that you would have to do it again until an upgrade.