No problem, and I forgot about that, good luck on your work.
Do you make sure you format the code correctly when referencing to your variables?
I try my best 
But I am somewhat new to ROBLOX (1 year experience).
Okay then make sure you do and keep up the good work! 
I have not finished the coding myself (working on it today), but I am linking the part that would be the teleporter (in my case, a jump ledge) to the landing spot via an ObjectValue. This way, I never have to hard code what two ledges are paired, and the character never takes a nasty spill into the ravine.
Applying my solution: in Stage 5, I would include an ObjectValue named “NextLevel” pointing to the starting point for Stage 6. No guesswork. You just finished here? Then you need to go here.
Alternatively you could also use an array with the levels hard coded, though the other solution would probably be best.