PPF can be entered as Other Asset from Data Management >> Create Transaction menu >> Other Asset tab >> Click on Create Asset button.
After submitting the initial Purchase and Current value, you can use the actions on the right of the table to enter additional Purchase/Sell transactions and Current Value as on different dates as and when you get to know them.
We don't calculate the current value of PPF ourselves by using the prevailing rate of PPF offered. So, using the Other Asset module you can enter Purchase, Sell transactions and Current Value of PPF from time to time. The same will come in the Portfolio report as well.