Use KGSynth in any DAW
KGSynth was originally created for MPC users, but the good news is that KGSynths can be used in any DAW at no additional charge! Basically, you need to run Akai's free MPC Beats software as a plugin within your DAW, then load sounds from there. (Note: KGSynth is not affiliated with Akai)
Simply follow this step-by-step guide!
1. Install MPC Beats (Free)
Akai's MPC Beats software is the free, "lite" version of their full MPC software, available for Mac and Windows. Click the "Free Download" button here and run the installer after receiving it in your email.
2. Load MPC Beats inside your DAW
Open up your DAW of choice (Ableton Live is used in this guide). Locate the newly installed MPC Beats within your list of plugins and load it into a track.

If MPC Beats does not appear in your plugin list, rescan your plugin folder. If that does not work, locate the folder that MPC Beats was installed into and direct your DAW to use that folder as a plugin folder.
3. Install KGSynth within MPC Beats
Simply drag and drop the "KGSynth Essentials.xpn" file into the newly opened MPC Beats plugin window. Pull up the Expansion Browser with the button on the bottom right of the window (red circle), click on KGSynth, and expand the "Programs" dropdown. This is the list of KGSynth sounds.

4. Load a KGSynth
Double-clicking a KGSynth of your choice will load it into the MPC Beats Project. To play it, click the keyboard icon under the Track section in the left-hand panel (red circle). This changes the track type to a "keygroup," which is what KGSynths are.
You should now be able to play the KGSynth using your MIDI controller!

If the KGSynth does not respond, you may have to manually select it under the Program section (blue circle). This assigns the Program (the KGSynth itself) to the Track. Additionally, if you load multiple KGSynths into this project, this is where you can go to select which one you are currently playing.
As a bonus, you are now set up to use any other MPC Expansions you encounter if you like them. Just drag them in and load them up!
Editing KGSynths
While KGSynths sound great out of the box, you are encouraged to flex your sound design muscles and make them your own! To make edits, go to Program Edit mode either by clicking the icon or locating it in the dropdown menu.

The Program Editor appears in the bottom panel. For the best visibility, turn off the Q-Links and Pads view (red circle), as well as all views except "Bottom Panel" in the lower icon bar. It is also recommended to switch from "Grid" to "Wave" view (blue circle).

In the Program Edit view, you will find synth parameters familiar to most synths, such as filters and envelopes. You can make adjustments just like on any other software synths. For more detailed information on now the MPC keygroup engine works, consult Akai's software manual.
One note: In KGSynth, the Sample Layers section is the oscillator section, so KGSynth is essentially a four-oscillator synthesizer using Akai's keygroup engine. This is where you can choose oscillators, set individual levels, panning, etc. If you need to make more detailed edits to an individual oscillator, you can make them in the Wave edit section at the top, which will reflect whichever oscillator you have selected at the moment (here Layer 1 in light gray).
Using Multiple KGSynths
If you only want to use one KGSynth on a track, you're good to go! If you want to use more than one on a track, it's important to understand a couple of things about MPC Beats. For starters, you can only run one instance of MPC Beats at a time. However, this does not mean you can't use multiple KGSynths on the same track.
MPC Beats (as well as the full MPC Software) is a DAW in and of itself. When you load it as a plugin within your DAW, you are essentially loading a DAW within a DAW. MPC Beats will allow you to load up to 8 MIDI tracks (with their own sounds). You can also think of MPC Beats functioning as a virtual version of an external sound module inside your DAW. Essentially, you can control these different sounds from your DAW independently by using different MIDI channels per track.
To set this up, navigate to Track 2 with MPC Beats. Open up the dropdown menu next to the arm button (red circle) and select "All," which reveals additional Track settings. Change the Input Channel to 2 (blue circle) and the Monitoring status to "Merge" (green circle). This puts your second track on a separate MIDI channel (you should also change your first track to Channel 1), and the Merge status means that it will play regardless of whether that track is selected at a given point in time inside MPC Beats.

Within your DAW, create a second MIDI track. Using whatever MIDI routing is available in your DAW, select MPC as the "MIDI To," destination, and specify "2-MPC Beats64". This means that this MIDI track will send all MIDI data to MIDI Channel 2 within MPC Beats.

Repeat this process for up to 8 tracks. For more information on using MPC or MPC Beats as a plugin within your DAW, refer to Akai's guide.
Most importantly, have fun!