Aware that this is dredging up an old post, but have just experienced this issue too.
For various rasons had stuck on an old version (2.4.6) and have recently just tried to upgrade to the latest version.
We use powerpoint presentations a lot, and rely on the presenter view appearing.
We too have found that in later versions, up to and including the latest version, that OpenLP is disabling the presenter view.
Is there a way to overcome this with the current versions, or will it be re-instated, or even as a setting in v4?