Much of what acer wrote is correct. Since Maple 2015, we've made updates to various plot commands to improve the error-checking and to use floating-point rtables for storing plot data whenever possible. There are still omissions in the documentation and inconsistencies in the commands' behaviours which need to be addressed.
First, it is a bug that plottools:-rotate accepts a non-real number for the angle argument. In the code, execution of F(t) should generate an appropriate error message. The fact that it didn't in early versions of Maple 2015 is unintended. It is also true that the help page needs an update. Similar commands like plottools:-scale and plottools:-translate do say that parameters must be real numbers.
Second, acer's example with plottools:-line is also a bug. This should result in an error, as the plottools:-polygon example does.
Finally, an easy fix to avoid premature evaluation is to change
and similarly for G.