One of the reasons that the wallet is long to sync and freezes is because it's based on a super old fork of Litecoin (0.8.6 to be precise).
The next major version of litecoin (0.10.x) contained a bunch of optimizations to improve syncing speed and db optimizations, so to improve our wallet we should rebase our code against a newer version of litecoin.
I started this work here, but if someone wants to continue, i suggest using my repository as a starting point https://github.com/Worldcoin-Network/worldcoin as I've stripped out much of the unnecessary skinning that the worldcoin QT wallet used.
The wallets that are posted in this repo do not have hardcoded seeds that currently function so you'll need to provide a worldcoin.conf file with nodes in them.
I do suggest caution about installing random executables so I recommend building from scratch (windows is a pain in the ass though, and best built by cross compiling under linux). Building for linux is dead simple.