ok, moving on to your lowpass filter section:
you're multiplying the cutoff by 11025 but the cutoff doesnt work in Hertz, it works from 0 to 1 where 1 corresponds to 22050Hz. I can easily change the cutoff to work in Hertz but I think it is better to work in zero-to-one as often it avoids additional multiplications/divisions. For example, an ADSR output works from 0 to 1, when it is controlling the cutoff of a lowpass filter it can be directly connected to it. As a general rule in synthmaker, units go from zero to one.
You're also adding cutoff with cutenv and cutlfo. It's a good idea to combine those 3 but when you add values in frequency you get results that vary as you go up and down the scale. For example, 1KHz cutoff added to a 1KHz cutenv would generate a cutoff at 2KHz which is one octave above while 2KHz cutoff added to 1KHz cutenv would generate a cutoff of 3KHz which is not 1 octave above 2Khz, to be one octave above it would have to be 4KHz.
A better aproach when controlling the cutoff of a filter is as in the example schematic that loads with version 0.9.0h, basically it works by adding pitch and converting to frequency. Pitch is similar to midi notes with 57 being 440hHz, each time you add 12 to pitch you're moving one octave above or doubling frequency. Adding pitch is similar to mulptiplying frequency, for example multiplying frequency by 2 is the same as adding 12 to pitch.