Quick and dirty hack to practice Technodrome spawns on flash carts. The location gets put into your high score as the tenths column, after you kill one enemy. 2 is the best spawn.

New improved version. Puts the value into high score instead of score. This also doesn't seem to have the overflow issues from before, so enemy spawns are normal.

You will need an ips patching program like Lunar IPS ( https://www.romhacking.net/utilities/240/ ). It will apply the patch to a rom file that you then transfer to the everdrive and run as you would any rom file.