As all the track is flex apart from points, to rough it out I will use flange head short screws fixed between sleeper with the head covering 2 sleepers to temporarily hold in place and make adjustments, should I put something like a 0.5 to 0.75mm gap in each join to allow for expansion, or am I overthinking it ?
As its only me second proper layout, and its the first in a shed, I thought maybe those of you much more experienced in these matters could help me avoid making costly mistakes

Oh and apologies mods if this is not the correct section, I couldn't decide where was !