@marpet thank you for your insights. To summarize my situation at this point in case this is useful by someone else:
What I want to do?
Update SNAP from 8.0.0 to the most recent version as of today (8.0.5)
Why?
SNAP v. 8.0.0 has some known bugs which affect the download of S1 orbits, DEMs, etc. Those where solved in SNAP 8.0.4. The SNAP official download gives you access to major relases (8.0.0). Small updates are done directly in the software.
What issue am I facing?
I am working behind a company proxy. Although SNAP has several ways to set the proxy configuration, it is not been considered and every time I try to update I get a proxy related error.
What have I tried?
Setting the proxy manually in the GUI in Tools -> Options -> WWW
Setting the proxy in gpt.vmoptions file located in ../snap/bin/ folder
Setting the proxy in the snap.conf file in ../snap/bin/ folder
Setting the porxy in the core.properties file in ../AppData\Roaming\SNAP\config\Preferences\org\netbeans
What is the current situation?
As of now my proxy settigns are set in all this files at the same time. SNAP is still unable to update
Any alternative?
Based on previous posts in this forum the only shot I can think of now is to manually download the updates and install them. I will test that next.
Any relevant post to considre regarding proxy and SNAP?
I summarized my findings in the forum in this other post:
Conclusion
Based on other comments in this forum and my experience, the way SNAP handles proxy is really creating issues for those working behind strict proxies. Would appreciete if some effort can be put to improve this.