My understanding is that the shop upgrades the workshop dice. The numerical upgrades are for the left one, the modifier ones are for the right. When in the workshop, you roll these two dice and choose to apply what you rolled to the main scoring dice.
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yep, sorry for the incomprehensible incomplete game, I didn't have enough time to finish it.
If you need more indication on how to play, I'll probably get the game updated in a few weeks, but basically yeah, you roll the normal dices to get points, that you can then spend on rolling the upgrade dices which... upgrade the dices : The effect dice tells the effect you're gonna apply on a dice, and the numbered one tells you the amplitude of the effect. Then, you can go in the shop to buy new faces to the upgrade dices.
Hope that helps, ...6 days later... but hey, thanks for trying it anyways !