Hi Goran,
I see no reason why the Troll fork wouldn't work just fine. I have that same fork on a Nashbar aluminum mountain frame where I use trekking bars and it rides very nicely. The Nashbar frame is designed for 80-100mm suspension forks I believe. My normal riding position is with my hands approx 1 inch (2.5 cm) above the seat. In that moderately upright position all is okay. The Surly Troll was actually suggested and installed by a local bike shop. They left me with the impression that you don't have to nail the axle to crown distance exactly. Just put things in reasonable range. It's a shame you didn't get help at your local shop. I can do a lot myself but when I need support I go to a shop that is very good at repairs and rebuilds. I then try to leave everything in their hands if I like their recommendation (purchase parts through them and let them do the work).
Mitch