That would be a good bet. That said I’m curious why you need adapted parts for resistors and capacitors though, they are standard parts.
Unfortunately no, there are two types of bypass capacitors and C1 C2 and C4 need to be 10uf for the regulators to supply peak currents. The .1uf capacitors are to eliminate high speed noise (which the 10uf caps won’t.)
Usually not a good idea. You want a higher voltage than the supply for the capacitors usually.
You want at least as many (it looks like 3 from the photo of the mega) as the arduino folks used (although you need to check the bottom of the mega board for more bypass caps that don’t show in the top photo!)
It looks from the photo that it indeed doesn’t need to be that close. I expect the routing still wants to be as direct as possible. At worst the CPU won’t work when the boards are made which means you will have to redo the boards. Can the components all be moved around to simplify the routing? Is there any thing that needs to be where it is on the board for external reasons? If not, when you have cleaned up the temp directory I’ll have a look at routing the board in minimal space.
I think you may have routing database problems, some of the rats nest lines in pcb are acting strange. That said here is a sketch with what I think are the correct bypass caps (I added 2 .1uf caps, one for the 3.3V regulator and one for the atmega.) As you will see I removed all traces and all vias (and the text) to start from scratch. As well I moved things around to make routing easier and the distance to the crystal shorter while hopefully leaving room to run the power connections. I’m assuming here that there are no physical constraints on the board (i.e components can be moved to simplify routing.). The power and ground runs from the regulator still need to be routed, but this is a likely safe bypass cap layout for both the regulators and the cpu.
ARDUINO-MEGA-MINIMALISTE-Fritzing-V0.22-xtal-bypass-caps.fzz (54.7 KB)