Command Block not Placing

So I was staring to make a function - adventure thing, and when I was trying to make a ground crafting recipe, using /setblock command to place a custom command block, it kept on not working! Maybe it's something to do with too much of the "{ }" brackets, I'm not sure. What's really infuriating is that the command works when other commands are inputted into the data tag.

By the way, there is a dummy scoreboard objective called Activation.

The Command That Must Go Inside The Command Block (raw) But Refuses to With the Setblock Command:

/scoreboard players set @e[type=item] Activation 1 {Item:{id:"minecraft:nether_star",Count:1b}}

Full (setblock) command:

/setblock 0 60 0 minecraft:repeating_command_block 1 replace {Command:"/scoreboard players set @e[type=item] Activation 1 {Item:{id:"minecraft:nether_star",Count:1b}}"}

The Error : Data tag parsing failed: Expected '}' but got 'm' at: ...ype=item] Activation {Item:{id:"m<--[HERE]