Syskit Insights cannot add certain (SharePoint Online) pages when using the web application.
Summary: The problem appears when the user is using the web application to add a site for which he/she does not have permission. In most cases, this will happen with a SPO (SharePoint Online) site. To be more precise, the problem lies with the authentication process for the given site. If you already have the required permissions, eg. for a on-premise site, you should be able to add the given site.
Solution: You should always use the Syskit Insights desktop application when adding new pages for Page Performance monitoring.
Number of processed servers during the scan is incorrect.
The problem may appear when scanning a certain Organizational Unit(OU). For example if you have an OU named SharePointFarm with 7 SharePoint servers, but a SQL server is located in another OU. The message during the scan will say: "Processed: x out of 7 servers." While in fact the number of discovered servers will be 8 (because of the SQL server).
After the discovery process is finished go to the Alerts tab -> click Manage. Locate the Farm in which you have missing servers -> click Add Server and manually add the missing server. You will need to provide a Server Name and a Server Role(s). For more information on how to do this see this article.
Performance counters graphs are "incorrect" for a period when agent was sleeping.
Summary: The problem appears when Syskit Insights is installed on a laptop, and when laptop is put into sleep mode. Personal computers (PCs) and servers (which does not have a sleep mode), are not affected by this. What happens, is that when you turn on the sleep mode, Syskit Insights Agent will "remember" the last collected value and "copy" it for every other performance data collection interval. There is no extra work done on a database so you do not have worry about that. The Agent starts to save new values the moment you turn on your laptop.
In the picture above the laptop was put into sleep mode at 16:00h and it was turned on the next morning at 08:00h
Solution: There is no workaround.