Hi nunoknic,
I have the same problem (1064: Something is wrong in your syntax...). My ISP update MySQL to a new version that supports balanced load (3.23.24) and this version have a new reservated word (fulltext). Change the word fulltext in the database to a similar word (fullatext, fullbtext, ...) and replace it in the code of PhP-Nuke too and That's all folks!!!!!