Hi, I am building a cut down version of PICDEM FS USB to enable
me to test a little bit the pic18f4550. I don't want anything fancy
 because I am working on one of those "block" type breadboard.
Sorry, but there are many questions, as I am a beginner.

1. the schematic specifies 2 x 22p for the xtal. However, the datasheet
of the xtal I purchased specifies 30p. Which should I follow?

2. C10 to C13 are 0.1u. Are they 0.1u each or together, and do I
absolutely need 4 x 0.1

3. C14 is 470n, as I don't have one, would 3.3u electrolyte be ok
(I also have 1u tantalum?, is this ok? better than 3.3u?)

4. is it ok to leave U2 pins 20, 21 floating, as I am not implementing
a power supply circuit. If both are 0 it will be "N/A" according to
table 1-1, but will it make the firmware/software crash?

5. i tried to program the pic with the factory default firmware
but is failed in the "verify stage" , so I programmed just the boot
hex and then it worked. Will I be able to use the device boot
loader when the demo firmware is not present,
and why the programming of the factory default failed.

6. I am not using IDE, but on the schematic third page (figure A-4)
it seems RE0 is connected to 5v. We also have RE4 on the pic,
so do I need to connect RE4 of the pic to 5v?

7. In figure 1-2 the clock is converted from 20mhz to 4mhz. If so,
why don't we simply use a 4mhz xtal (internal?)?
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