They need to be full leveled, u need to put all the points on there stats so that u can use the upgrade.

Make sure u have no more lvls to get on them

Psycho dont need to fix, you just did it wrong

make sure the xp bar on reaper / tribesman is only one number . EX : 10,000 / 9.980 (varys to what ever your max dino xp is)

By using the supreme xp potion it is fully leveled instantly and I indeed spent all of its skillpoints. It shouldve worked and it just didnt.. Im only a little mad about the resources coz its not the cheapest.. so let me cry^^

Ok, nvm.. think its a server sided issue... thanks tho ;)

so what was it , do tell , just incase .

it seems like the maximum amount of xp a creature can get is 1000000000( 1 billion ), after that the counter wont increment anymore. when you now set the maximum level of a creature too high ( in this case too high means a level that requires more xp than 1billion) the max level is never reached, although the creature wont be able to progress in levels

so was it getting the xp bar maxed or max level the dino ?

i only ask because my reaper is max level as is my tribesman , but the xp bar hasnt maxed out .

it couldnt max out both, coz the dinos xp bar didnt move on at 1000000000 xp and for the next level it needs 1000111552 xp, so neither xp can get maxed nor the level

I do have the same problem right know, what do i need to do?

For those who have set the XP grind to impossible heights; Use Nano Armory.
There is a Max Dino Level Potion as part of the mod that instantly gives a full XP bar with all levels to be applied.