The Resolution slider for ZigZag doesn't work with World on Realms

Overview

When using the resource pack ZigZag I purchased from the Minecraft Marketplace in my world on Realms, I am unable to change the resolution slider from 128x for the resource pack. Changing the resolution slider to 64x or 32x is not honored in my world in Realms. It stays stuck at 128x.  The ZigZag resolution slider works fine with local worlds. Steps are below:

Steps to re-create

A. World on Realms (slider doesn't work)

1. Launch Minecraft
2. Select Play
3. Under the Realms section, select the Edit button for your world with ZigZag enabled in Realms
4. Select the Active World for the Realm (should have a green checkbox in the tile)
5. Select the Edit World Button
6. Under Add-Ons, select the Resource Packs button
7. Select Active
8. Select ZigZag
9. Select Settings (gear icon)
10. In the ZigZag settings window grab the Resolution slider and move it to 64x or 32x (see image ZigZagSettings_Part 01.png)
11. Select the x icon to close the settings window
12. Select Back (looks like a "<")
13. Select Play
14. Once game loads, notice that the graphics don't look any different (see image ZigZagSettings_Part 02.png)
15. Press Escape
16. Select Save & Quit
17. Select the Edit button for your world with ZigZag enabled in Realms
18. Select the Edit World Button
19. Under Add-Ons, select the Resource Packs button
20. Select Active
21. Select ZigZag
22. Select Settings (gear icon)
23. The setting has reverted back to 128x (see image ZigZagSettings_Part 03.png)
24. Slider is not working as intended

B. World Saved Locally (slider works)

1. Launch Minecraft
2. Select Play
3. Under the Worlds section, select the Edit button for your world with ZigZag enabled
4. Under Add-Ons, select the Resource Packs button
5. Select Active
6. Select ZigZag
7. Select Settings (gear icon)
8. In the ZigZag settings window grab the Resolution slider and move it to 64x or 32x (see image ZigZagSettings_Part 04.png)
9. Select the x icon to close the settings window
10. Select Back (looks like a "<")
11. Select Play
12. Once game loads, notice that the graphics do look different (see image ZigZagSettings_Part 05.png and then compare to ZigZagSettings_Part 02.png)
13. Press Escape
14. Select Save & Quit
15. Select the Edit button for your world with ZigZag enabled
16. Select the Edit World Button
17. Under Add-Ons, select the Resource Packs button
18. Select Active
19. Select ZigZag
20. Select Settings (gear icon)
21. The setting is still set to 64x or 32x (see image ZigZagSettings_Part 02.png)
22. Slider works as intended