Rights issue and preferential allotment

XYZ LTD is a Unlisted Public Limited company. It wants to infuse further equity. It makes a Rights issue at par. The Rights issue is made as 5% on application and the rest in calls as and when decided by the Board.  

Is there any pricing guidelines to be followed for pricing of rights issue? Can Rights issue be made at par.

While the calls on the rights issue are still to be made , XYZ Ltd wants to make Preferential Allotment under Section 81(1A) at a premium.

 Is there any restriction?

Kindly advise.

Thanks