Sorry if it's troubling you.
modmii is fine, as it doesn't modify the existing files, it only adds new ones. It just adds unnecessary files, but you don't have to worry about that, as it will also install the things you need.
Here is the tool you need if you don't want to use modmii:
(you don't need modmii anymore if you already installed HBC and made a dump of your NAND)
D2x cIOS installer - Full package for Wii
Extract it to your SD card, in a way that you have the "boot.dol" in a "d2x installer" folder.
For example :
sd:/apps/d2x_installer/boot.dol
sd:/apps/d2x_installer/icon.png
sd:/apps/d2x_installer/meta.xml
sd:/apps/d2x_installer/ciosmaps.xml
sd:/apps/d2x_installer/7/
sd:/apps/d2x_installer/8/
sd:/apps/d2x_installer/10/
put on Wii, launch the installer.
note that you'll need the network enabled, as you'll download files from Nintendo's servers.
In the installer, choose this :
What : d2x v8 Final
Where : 249
Base : 57
Version : 21008
Press A to install, and wait until it's done.
Exit with Home button, that's all
You'll wonder why v8 instead of v10 ?
v8 is latest stable release.
v10 is a copy of v8 but with a little fix for HDD detection. if v8 works, you don't need v10.
v10 (r52) = V8
v10-alt (r53) = v8 + USBPort1 support, but EmuNAND support is broken.
If you don't need to connect 2 HDD at the same time, you'd better install v8, you don't need v10-alt.
About the "base" :
Lot of guides make the users install different cIOS with different bases, just as common practice.
a custom IOS is based on an official IOS, it adds patches, and install the result in a new slot.
cIOS based on IOS56 works fine with all games needed IOS56 or lower, but games which usually require the official IOS57 will not work with the base56 (as it miss some functions).
It's best to just install a cIOS with the base 57 (working with all games), instead of installing both cIOS[56] and cIOS[57] and switch to 57 when a game is not working....
But it's up to you.
If you want to have the same setup than lot of users, you can do this :
What : d2x v8 Final
Where :
249
Base :
56
Version : 21008
What : d2x v8 Final
Where :
250
Base :
57
Version : 21008
by default, USBLoader will use the slot249 (which contains the base56), some games will not work and you'll have to set the slot to 250 for these games in the loader's settings.
You asked about burned disc :
Just know that NOT all consoles are compatible with DVD-R.
you must be sure Burned discs are working first.
the old method to use burned disc was to patch all IOS (like I explained above, using pimpmywii or DarkCorps tools). but it's now working fine from USBLoaders without patching ANY of the IOS files.
insert the game disc and see if it works.