Tried your 3.49 version in v4.12.2 and 4.13.4 without any problems.
About 4.14...I don´t think it is worth the effort. 4.14 it´s not going to be used by the modding community. TD has made many changes against the modding community as this one you´ve found. So the result is 4.14 it´s not compatible with many mods and it makes the modder community to "start" again from the beginning., it´s not worth it.
4.14 it´s not going to be used by many people only by the players that doesn´t use any mod (and this is a very, very low percentage of the users base)
Also, 4.14 hasn´t got any useful code improvements, just two maps and really, nothing more :(...TD has killed IL2
Lowengrin, If I were you, I won´t try to update the DCG to 4.14. Just keep upgrading and debuging it as it is a marvellous add-on.