The S1TBX issue is not solved with this update, because only the SNAP core was update but not the S1 Toolbox.
The error you see is tracked in this ticket
[SITBX-847] Error “WstxInputFactory not found” caused by s1tbx-cloud module - JIRA (atlassian.net)
As far as I know this is only solved in for the next major release. And is not included in an update.
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