The databases for gtktide were missing a lot of international tidal stations. Xtide typically has a lot more stations and a graphic version would be fantastic. What tide database are you using in your build?

I'm running the Palm OS emulator (Garnet VM) and inside it I've installed Tide Tool 2.2 (http://www.toolworks.com/bilofsky/tidetool/) which uses the Xtide 2.6 database with 7000 locations.