Describe something as "weird" makes it very hard to understand what you believe the problem is, can you try and describe better what the issue is?
@Bolli has been working on cars so there's a chance he knows what's wrong but if you can be more descriptive I am sure it would help
This is not how the multiple credits work, 3 credits does not mean your bet is 3000$, it simply means that if you hit that row the 1,000$ bet will be multiplied by 15 instead of 5
This is working as intended