It all depends on the device you're using. If the Flux Player is a multimedia device, storage increase can be done by deleting other content since you don't have access to the file system, and even if you did, there is a very low chance that if you delete items will actually increase the storage.
Additionally, if the Flux Player is running on a PC, then you have to make sure that the installation location has enough space, or you use a path where there is enough space.
For this particular reason, simply use CCleaner to delete junk data.