Do you use a startpos from NTF? If this is the case you cannot do this because they are playable only in their own mod folder (NTF). It is possible to use them for in mp_eur_napoleon only if you make the next changes:
Replace the NTF with mp_eur_napoleon in the following 2 places in startpos:
1. [..] CAMPAIGN_PREOPEN_MAP_INFO/
2. [..] CAMPAIGN_ENV/CAMPAIGN_SETUP/











