Here I am going to tell you how to turn Rainlendar into a hideable/showable Sysmetrix dock. The process is rather simple actually. first, find a button on your sysmetrix skin that you dont use that looks appropriate for a show/hide button. then go into your skin properties in Sysmetrix, find that button in the menu(or add it) Change the description to System-External Program. AT the botton of the config window myou will see a section labeled external program information. click the ... there and select your Rainlendar exe, which is by default in C://Program Files/Rainlendar. in the parameters field type !RainlendarToggle. in the Working dir. field type your rainlendar directory. eg.C://Program Files/Rainlendar NOT C://Program Files/Rainlendar/rainlendar.exe. Leave state at normal.
Now for soem theoretical fun, if you had a vertical sysmetrix skin, you could place it on the right side of the screen and make a large vertical button with a left arrow on iton the left side for the dock button. also there might be a way to make Rainlendar appear to slide in and ou of Sysmetrix, if there is, idk about it.