Thank you for the report.

I check the source code and found it Previous / Next strategy features takes the current strategy as a reference (as expected).

However, when we change the Collection, the program may not find such a strategy in the new Collection as a reference point and simply rejects the operation.

I uploaded an update, which loads the first strategy from the new Collection in such a case.

I am having the issue again, it won´t load any of the next/previous strategies, although there are 19 in the collection. Here is what I´ve done to arrive at the problem:

Optimized an existing strategy while adding all optimized results to the collection. This created 19 entries. I´ve then changed the data horizon (shorter) and clicked Recalculate in the Collection. Then I´ve made the data horizon bigger again and clicked Recalculate again. After this, it´s impossible to switch between strategies once again.

Hello GeekTrader,

The Optimiser pushes strategies with the same major ID number (the number before the dot) and different minor ID numbers when we use "Add the optimized strategies to the Collection".

However, it appeared Ctrl + -> cycles through major versions only, which explains your issue.
Now I removed this limitation and it cycles through all the available strategies.

I don't remember why it was like before. Anyway, please test it. If it needs additional fixes we will do it.