Hi @Willemb,
Sorry to hear that!
The Probes, Probe Tips, and Desiccant Bags can be bought separately, which is helpful if they get wet or damaged and need replacing 
We have a reasonably extensive Operation Guide which includes a pre-dive checklist and recommended maintenance.
If the pre-dive checks are completing successfully then it’s expected that the vehicle should be good to go
Potted penetrators are challenging to install consistently (especially at scale), and can at times fail somewhat unpredictably, which is a big part of why we’ve stopped using them on our products. I’ll direct you to this comment for more info
Great to hear! 
Indeed - leaks in something like an enclosure often at least start out slow, so having an early warning system is super helpful for avoiding major failures due to water damage