Hello,
The unallocated space partition is normal as you have just installed the OS but have not yet booted the Shake up with this new installation.
Once you do it, the Shake OS will automatically resize itself to adapt to the microSD card in use, naturally leaving other free space to store the data the Shake will record.
If the gaps in the stream reappear, or there is anything else that seems not to be working fine, please download the logs (instructions can be found here, if needed: Please read before posting!) and post them here.
You’re welcome!