You need to convert the NRPN numbers to their MSB LSB representation. It’s fairly simple (if you google someone might have made a gadget to do it automatically) but can be fairly tedious - I’ll try to explain what’s going on, and then give you a shortcut for working it out.
Basically, if you convert the number to binary (padded with 0s on the left to make it 14 digits if necessary), the MSB = the number represented by the first 7 digits, and the LSB will be the number represented by the last 7 digits.
So, for NRPN 2, this is 10 in binary, and padded with enough 0s we get 00000000000010. So the MSB is 0000000 in binary, which is 0 in decimal, and the LSB in binary is 0000010 = 10, which is 2 in decimal. This reveals something that’ll make it less tedious for you: 127 in binary is 111111 - eg. the highest binary number with 7 digits (this is significant because CCs go up to 127, and you send an NRPN by sending a sequence of CC messages).
So for NRPN x, where x is between 0 and 127, your MSB is 0 and your LSB is x. You can use this fact to work it out without the binary conversion: your MSB is how many times you can divide the NRPN number by 128 (with some remainder x) with your LSB being x modulo 128 (if you don’t know what modulo is, google’s built in calculator will compute it for you if you type the expression into the search bar, but x modulo y is equal to the remainder you have when you divide x by y).
So in the NRPN 2 example, 2 is divided 0 times by 128, with remainder 2: your MSB is 0. 2 modulo 128 = 2, so your LSB is 2. For NRPN 300, 300 modulo 128 is 44 (this is your remainder). 300 - 44 = 256, which can be divided 2 times by 128 (2 is your MSB). 44 modulo 128 is 44. So NRPN 300 is MSB 2, LSB 44.
The pattern you’ll see is
NRPN between 0 and 127: MSB = 0, LSB = the NRPN number
NRPN between 128 and 255: MSB = 1, LSB = the NRPN number modulo 128
NRPN between 256 and 383: MSB = 2, LSB = the NRPN number modulo 128
NRPN between 384 and 511: MSB = 3, LSB = the NRPN number modulo 128
…
and this continues up to the maximum NRPN number. Looking at the. Rev 2 manual, you only really need to go up to NRPN 187, so most of this doesn’t need to be worked out, and up to NRPN 127 there isn’t anything to work out.
Oh and important extra note: what you tried to put in is the range of that NRPN number, not the NRPN number itself. The important number to use is the one in the left side column. You may find if many NRPNs have a limited range (eg. 0-200, out of a possible 16384), it’ll actually be kinda hard to use the Hapax grid to put in modulation, because basically the addresssable range of that parameter is all going to be contained on the bottom row of the grid - I asked them about adding range to instrument definitions, and scaling the grid appropriately, and I really hope it happens.