Rapture LE: inputing Pitch steps with MIDI Keyboard when Depth exceeds 2400?

I am running Rapture x64 LE Version 1.22
 
I wanted to build an arpeggio which spanned almost 3 octaves. So I set the Depth at 3600.
 
I inputed the steps via the keyboard through the "normal" procedure (MIDI Note Entry C4=base).
 
All I get is crap because Rapture lets you use only 24 keys on your MIDI Keyboard (those being C4 - C6) to cover the whole interval set by Depth (in my case 36 semitones). So when I press C4 it inputs indeed C4, but when I enter C#4, it inputs a note higher than C#4.
 
To be more specific: I set the Depth at 4800 (4 octaves).
Now press key C4 and it inputs indeed C4.
But then, press C#4 and it inputs D4.
Press D4 and it inputs E4.
Press D#4 and it inputs F4.
 
So what it does is that it divides the interval that you define with Depth to the 24 keys available.
 
With all due respect, this is such a SH*T and FU**ED UP nonsense.
 
If I am wrong, I appologize in advance, but I think I'm right. 

Thanks for the articles, and they are very interesting (in fact, I'd already seen them when I searched the forum).

However, they don't solve my problem.

How do I input "exact" notes when Depth is, say, 4800? Using the 24 'legal' notes (as they're named in one of the articles) causes a mess. Because we then have 24 keys to draw in 48 notes...

Inputing via a MIDI file causes the same.

I tried "Extract Shape from Sample File" (I first created a wave file, some distinct, simple phrase played with a sine wave oscillator, so as not to "confuse" the Step Gen in Rapture). But that won't work either.
Any other suggestions?