japanese keyboard entry

I'm trying to make my scripted objects Japanese-friendly, so I've asked my translator for things that are easy to type on a Japanese keyboard. For testing, I've done two things. I've added Japanese entry as a second language option in XP, so I can now type Japanese characters on an English keyboard, and I've ordered a Japanese keyboard.

Typing Japanese on an English keyboard seems to offer a lot of different ways to type. I'm wondering two things: is there a standard way to interact with SL, and does that change if you have a Japanese keyboard?

Here's an example...

Scripted objects often respond to commands typed on a specific channel, and to type on a channel you prepend what you want to say with a forward-slash and the channel number. For example, to get my flight assist command summary, you'd type

/31 help

With the default XP Japanese language support using Microsoft's IME, the easiest way to type that is probably to switch to English input mode (alt-tilde), type it, then switch back to Japanese input (alt-tilde again). And as far as I can tell, even if I create a Japanese-language keyword for 'help', you'd still have to switch to English to type the /31 in half-space alphanumeric mode, or you'd have to type it then hit the space bar a couple times to get IME to switch it, or you'd have to have IME set up to do that by default.

So, my questions...

1) Is that what Japanese typers on an English keyboard have to do to communicate with scripted devices, or am I missing something simpler?

2) I understand Japanese keyboards have a key to switch modes easily. Is it still necessary to switch to half-space alphanumeric mode to type a channel number (/31) in SL?

3) Would it be easier to type the English commands, or would it be helpful to have Japanese commands. That is, would it be easier to type

/31 menu
or
/31 メニュー

4) My translator says it's easier to type upper-case English letters, which would seem to mean IME is used to quickly get English letters (by shifting them) without switching to English mode. Is that correct?

Thanks,
Anya

Most scripted objects I've found in Japanese sims use english words for commands and don't seem to make a big deal about it - though the words themselves are often romaji.

What effect would running a Japanese localized operating system versus an English localized operating system have on this matter?

Since my translator suggested only two katakana substitutions for chat commands, I decided to not use any. My list of commands includes Japanese descriptions, so I think this is best. I'd otherwise have two exceptions to an otherwise all-english command set.