@Gear maker Yes I an see what you're saying makes sense. I wonder if the developer could overcome that problem by incorporating a key combination to give more control over locking and unlocking the viewpoint ...eg Option + Command + Click or Shift + Command + Click? Since I'm only starting out I don't know much about the different commands and key control s yet....but as a novice user, on a Mac desktop, with a Magic Mouse....I'm immediately presented with difficulty; that doesn't make a good impression and it interferes with the use of the software straight away. Pluse, I shouldn't have to go to the expense of buying a mouse or trackpad for software that doesn't work on the systems it says it does work on.
Apart from that though, I'm sure the software is very good, perhaps if compared to Pixelmator, but it ain't that good if the immediate shortcomings impede its use! Might be inclined to seek a return!
Thanks again for your help