Four SBSs

Spoiler: shortcut

am I not supposed able to do that sbs
onto moving slider?

@Ray Aznable - That was @Pratik Bhalerao's shortcut as well. Good pick up...

...
what to be added for removing that SC?

@Ray Aznable - To be honest, I didn't even look into a fix when Pratik raised it...

Looking at the fix now, I can see a few ways to stop your opening move but without having a full picture of how the level played thru and all the potential misleading routes etc, I could be changing the game play.

If a had to fix it, I would probably add another metal rounded block and extend the stairs one block so if B hits the ball, it lands in the hole. With that said, I didn't play thru the level to see if the rest of the level works.

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@Meko Guy
from your explainations,
i thought the sbs onto moving slider
was the flaw,
turned out, it is this area.

Spoiler

I made a change based on ur reply.

Spoiler: ALTERNATIVE CARD

did that, to force myself
playing it intendedly.

@Ray Aznable - I made the same change here and when B drops that ball it lands in the hole but like I said, I didn't play the entire level to see if anything else was affected.

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@Meko Guy
nothing affect initial gameplay.

Spoiler

the addition keep the illusion of red herring