You must have Explorer-style mouse selection disabled in preferences.
https://winscp.net/eng/docs/ui_pref_commander
https://winscp.net/eng/docs/ui_pref_commander
1) When selecting multiple files, the first file selected isn't highlighted, thus I need to return to the first file after selecting the others.
2) Once selected, this version and the previous have an issue with de-selecting a selected file. Clicking on it does not remove the blue highlight.