Appointment problems are making my business non productive!

Problems keep popping up and it is beginning to get unnerving!

1. At the moment clients who are logged in and select an appointment, choose a date can not choose a time. The link to choose any of the times available.

2. When I set an appointment manually on the site it only blocks of 30 minutes.

3. When I block off time on gCal it still shows the appointment as available!

I am very frustrated! It seems that this plugin is made very poorly and ver juvineille. I do not understand how it has so many problems and yet was created years ago! There are sites like genbook and styleseat that work straight out the box without these problems, and though I did not want to resort to one of these services I am on the verge of doing so.
I have been having problems with this plug in form the inception, which I have many support history to verify. If developers can not give their attention to this product, I will request a full refund for the past 6-7 months!