Hello,
Check the Options page - there you can set what button should be used for scrolling and you can test there how it works (in the right part).
Best regards,
Juraj Mäsiar

Hello,
The left button scrolling is very hard to do right. The web is full of badly optimized pages so be careful if something stops working (like editing cells in web Excel/spread-sheets).
The text selection cannot be improved, but you can change the way you select the text - if you use "double click + drag" then the text selection will select whole words, not just letters. And triple-click usually selects whole block.
Using these two techniques should help you with text selection.
But I'm planning to improve the left button scrolling to be more compatible on web.

Best regards,
Juraj Mäsiar