Can I record contributions and pledge payments in a "Batch Data Entry" of type pledge payment?
While in 4.7.7 (sorry, don't have a 4.6.3 environment to test), it is technically possible to record stand-alone contributions in a batch created for pledge payments by leaving the "Open Pledges (Due Date - Amount)" field blank and selecting the desired financial type, in a recent session at CiviCON 2016, Joe Murray indicated that best practice would be to record each type of contribution with the batch entry category that it falls into (i.e. use contribution for stand-alone contributions and pledge payment for pledge payments), although I clearly see the convenience of being able to record multiple contribution types in a single batch entry.

Hope this helps,
Tamar