In VR Tourviewer, if you use _hidden as part of the ID or Skin-ID, the hotspot will be hidden. So if you'd like to hide a hotspot on web and not in VR Tourviewer, use a different name for the Skin-ID, like ht_hide or ht_invisible. Then you can use that skin-ID to create an invisible hotspot in the skin that will be used on web.
You can set the desired default look of the polygons in the 'Hotspots' rollout of the Pano2VR Output settings. Then you can decide per polygon if you want to use the default colors or want to use a different outline and fill color.
Note that the 'Alpha Channel' value in the color picker determines the transparency, where 0 is invisible and 255 is opaque.
A Beta version is not available yet, but to know if the upcoming update will work with your Cardboard, you could try the OBO VR app for Android or iOS. It's also available on Oculus/Meta App Lab
This app was created for the United States Department of State and is a customized version of VR Tourviewer. It uses the most recent Unity XR and Google Cardboard SDK that is also used for the upcoming public update of VR Tourviewer.
Thanks for reporting! It seems like a wrong VR Cardboard profile is used by the app. I've tried to replicate the issue here but I don't have the exact same phone model, it worked fine on a Samsung Galaxy S6 though.
I'm working on a major update planned for release in the 1st quarter of 2023. If you want I can add you to the Beta testers so you can test it as soon as the Beta version is available. If you can send me your gmail address in an email to firstname.lastname@example.org , I'll add you to the test team.