Ive figured out why the tool is so slow to use once youve made a decent length and want to move it. After some picking apart, and experimentation, i’ve found that if you go to the AddRoadToSpline function, set all the update mesh booleans to false on the set start and end/scale functions, it stops the massive lag when moving the roads around. I hope this helps everyone because it certainly helped me. Again, great tool Sieben - two thumbs up bro =)
**** Doing this will disable collision, so when you have finished setting the roads position, set the bool back to true. (I promoted it to variable and made it public for ease of use) ***