Also, the reason I came here initially wasn't to praise TMP, it was to check out and see what was up with the reloading tabs option. An option that works maybe 1 in 20 reload sessions. I have the option unchecked, meaning I do not want Firefox to reload all tabs when I restore a session. From what I gather this will be implemented correctly in a future version of Firefox. What's strange is that sometimes (rarely) it does actually work correctly, and sessions get restored with all tabs grey and not reloaded until I actually click on them (what is very much desired). So there must be a bug somewhere. Fix this and get TMP working with the option to not reload tabs on session restore correctly and TMP will be even better! If there was one bit of functionality I'd like to see working in TMP this would be it.
I have attached a screenshot of my Session settings in TMP Preferences because my tab restore works exactly like you are wanting with not loading until I tell it to load. I use Firefox's built-in Session system as the browser itself has this feature as of at least version 14.
So try my settings and see if that makes it work for you as well.