Would it be appropriate to use this in the context of asking somebody to speak more slowly so that you could understand them?
Yes, that's how I learned the phrase. You could also say "Sprechen Sie langsam, bitte" ("Speak slowly, please").
Kannst du langsamer sprechen, bitte? would be better word order here because of the modal verb "koennen" at the beginning of the sentence, which forces other verbs to go to the end in their infinitive form.
Another new phrase to shout during sex, aye? This should be in the flirting section.
It'd be correct to say this when a driver is going too fast? Please, if don't how is it?
Both, in German appears to be that adjectives (acording to the context) could be adverbs too
Bitte langsam, bitte langsam //
Bitte sprechen Sie ganz langsam //
Ich bin Ausländer und spreche nicht gut Deutsch
Why is 'slower, please' not a correct translation? Google translates it as 'langsamer, bitte'- why the -er?
Slow is one thing and slower is another, in english the termination -er means to amplify the root of the word, so "slower" mean that something is even more slow than "regular" slow.
Not sure the -er termination is about amplification. It seems to me that it might be about comparison. A person may already be speaking slowly, but if it's not enough you might ask 'langsam bitte' for a further slowdown
Not sure, though the -sam suffix is related to the -some suffix we have, so it's technically related to the "word" longsome
Its the same as in English words with "ng" in them, like "hang". Its not silent, but its different from the normal g sound.
No, just gutteral. You swallow it a little as you say it, with no inflection on it. Not lan-guh-zam, but lang-zam.
Is it possible to do only those tasks? I find them the tasks that i learn the most from.