Presumably if the modules are Part 147 Approved, completion of the course and training programme, could, if the training is considered part of the 5 years total experience, allow someone to carry out this course, complete a further 3 years OJT/experience in a Part 145 and then apply for a UK Part 66.
If this is the case there doesn't seem to be much benefit, it costs 26K euros plus expenses, for a Croatian licence. Much better to look at the established routes in the UK.