I was able to boost my trains and send gifts by trying a couple things. They may or may not work for you but worth a try.
1. Remove all Level 0 XP Neighbours from your Neighbour list and delete them from your friends list. Close FT, do Memcache, clear browser cache, close and restart your browser. Load the game and try again to send gifts.
2. Get your Neighbours under 100 - again do the memcache browser thing.
3. I also removed a few people from my friends list (about 200 - I only use FB for FT friends and they were no longer active) This may or may not have helped the issue, but it did help me maintain the list of people playing the game with me
I also have had issues connecting to apps.facebook.com with servers timing out and causing me lag, which would most definitely show the loading bars people see when waiting for their lists to load. Recently I have been connecting to another apps.facebook server and this may be the sole reason I am having better luck sending gifts and boosting trains now.
If you know how to do a trace route to apps.facebook.com perhaps it would not be a bad idea to see if you are also timing out trying to connect.