Introduction

This is a sample maths learning activity for learners to Drag&Drop matching green tile to the right slot. At the beginning all slots are empty and the green tiles are moveable. Learners can freely move green tiles to the empty slots or between slots as it feels fit. However, once Handed In the correct answers are displayed, the matched tiles are aligned, others are deleted.

Deployment matters

This learning activity works fine in Desktop Mathematica environment.

Firstly, can someone help me to understand how to make it 'deployable' using CDFDeploy and/or CloudDeploy ?

Secondly, can someone help me to understand and fix "access violation" exceptions it throws in Web Mathematica?

These are school boys' mistakes of mine. I feel a bit embarrassed please be merciful!

Technical notes

The implementation is in the attached notebook.

The code is straightforward: green tiles(myTiles) are visualisations of Dynamic Locators in the vector named pLi used in LocatorPane myLocPane. Please note I use LocatorPane[Dynamic[pL] as per documentation. Button Hard In has the following 3 actions: myState = False to set Enabled to False. mFontSize = 14 to display the correct answers and pL = CompleteTask /@ pL is my poor attempt to align matched tiles by setting x coordinate to be 0.5 for all i.e. Left alignment and modify y coordinates to be Floor[y, 0.1] + 0.05 to justify tiles vertically. There are 10 slots, thus 0.1 is used in Floor function, addition of 0.05 makes it Centered .