That reinforces what I'm saying. Some silicon based compounds are conductive and some aren't (silicon is the base for ALL semiconductors!). Unless you are absolutely sure you know how conductive it is (also applies to any other potion) then it shouldn't be anywhere near electronic connections (where even microscopic amounts of conductivity can cause problems). Most ECU sensors are still analog (i.e. they produce small voltage changes that are measured by the ECU) - eventually they will all be digital where the voltage measuring will be carried out inside the sensor itself making the system less prone to interference and connection issues.
AFAIK no manufacturer uses "gunk" on connectors (WD40, etc. etc.). In Hoverland (as in some other areas) it is used to compensate for poor design and/or choice of components - in other words, the product is not fit for purpose so the owner is left with high maintenance and poor reliability. First, as detailed in the marinisation guide, get rid of as many connectors as possible, secondly use automotive external connectors (not the in-cabin, unsealed types) and you won't go far wrong.
Of course, you still need to pay close attention to cable routing, cable protection and proper strian relief (look under a car bonnet for examples of good design practise!).