The collector object requires idx to save experiment results. In rl-control-template this index is set after the collector is constructed as follows:

collector = Collector( config=..., default=...,)
collector.setIdx(idx)

However manually setting the index forces a collector reset which sets the frame to -1. In order to load Collector checkpoints, I need to set the index in the constructor as follows:

collector = Collector( config=..., default=..., idx=idx)

I noticed setting the index in the constructor does not add this index to self._idxs and this causes an issue with saving results because saveCollector loops over self._idxs and will ignore the index set during construction.