Because you may be using Euro jurisdictional approved software versions, you may not be able to switch sjur chips. Class 3 gaming is not a mix and match proposition. Software has to be approved by specific jurisdictions and thus some regions require specific changes to the software. I'm not saying your particular version will not work with any other SJUR, I'm saying it is a possibility. Here in the US we have games that don't work in certain states because they have not passed jurisdictional approval, so the software version checks for approved jurisdictions and if the jurisdiction is not in the approved list, it will not work. You may be facing the same issue.