Analysis of brainvision analyzer eeg data in spm12

I have a problem with using brainvision analyzer eeg data in spm. Some preprocessing was already done in brainvision analyzer (I exported the data as mat files) but i want to go on with the rest of the analysis in spm. I tried to create a spm compartible file with creating an bdf file through eeg lab but to do so I had to concenate the already epoched data. And when I tried to create a trail definition file (to epoch the data later on) spm didn't recognize the event markers anymore. I tried to segment the data with a loop in matlab but then the output wasn't compartible with spm12 anymore. When I used the non epoched data from brainvision analyzer spm12 didn't read the event markers as well. Can somebody help me and has a solution for me? That would be great!