If you are cooking the cream and adding chocolate to it for your ganache it has a longer shelf life than you think. That is how I make mine and then roll into balls by hand before dipping them, get 3 months shelf life... even longer if stored in refrigeration. Your lollies crumbling sounds to me as though your chocolate is not tempered correctly and therefor has too much crystallization.
When using seed method if you over heat the chocolate you have to allow it to cool to less than 110F before adding seed and continue stirring till reaches optimum temp or even slightly less then warming 1-2 degrees to reach optimum working temp. If your intent is to mold then you don't want the mold warmer than chocolate, allow chocolate to set (65-70 degree room) then refrigerate briefly to allow choc to shrink from mold. Good luck, you did very well for your first time other than rushing. Good things are worth waiting for.
I make 8lb batches, toffee itself approximately 4lb into a sheet pan and allow to cool to room temp (68*F) then wipe off butter sheen with damp paper towel then dry towel. Coat with tempered chocolate using spatula, allow to set, then turn and repeat on opposite side, when chocolate is still tacky (nearly set) score with point of knife into squares, then allow to finish setting before breaking into individual pieces. This method produces very little shearing rarely any, maybe 1 in 20 batches will be problematic but not usually more than 1/8 of the batch. I make toffee with Milk choc + almonds (in this case the choc doesn't have to have perfect temper), Milk choc, White compound coating, or Dark choc + white drizzle and all sell very well. It is very dry climate here 30-35% humidity but even on days that exceed 40% I can make toffee without the chocolate from shearing off. I believe the key is in scoring the chocolate before breaking the piece, if the chocolate fully sets before scoring then it is more likely to separate from the toffee.
Old newspaper print or heavy Kraft paper is an excellent and cheap way to provide extra insulation inside of the mailing carton. Freezing the product prior to putting it in the shipping carton also helps. And if there is time prior to pick-up time put the whole package into freezer. This will extend the time that the package will be below point of melting. All shipping trucks and mail cars are metal boxes just like a convection oven (frozen items take longer to cook than refrigerated or room temp).
