You said that てくる also means present perfect progressive and add から is optional, I have one point I could not understand in one of your examples, 彼との why a との together? What does it mean?
I said that "~て きた"(not "~て くる") makes present perfect progressive,
if you want to make present perfect progressive sentences using "~て いる", you need a "since clause":
わたしは彼との友情を大事にしています。I'm cherishing a friendship with him.(Present progressive)
わたしは子供のときから 彼との友情を大事にしています。 I have cherished a friendship with him since I was a child. Or I have been cherishing a friendship with him since I was a child.(present perfect progressive)
"~との関係" means "relationship with someone".
http://eow.alc.co.jp/%e3%81%a8%e3%81%ae%e9%96%a2%e4%bf%82/UTF-8/
彼女はここに着いたときから、私が緊張してきた。Since she have come here, I have been nervous.
きみが緊張になってきたのは、学校の試験を休んで言い訳だと思うなら、いい大学に入ると思うな、なぜならさっきの試験はとても大事な試験だったのよ。
If you think that because of being nervous is a good excuse for having missed the exam, don't think you are going to enter in a good university as that exam was really important.
Those sentences don't make sense, though I know what you intend to mean.
彼女
がここに着いたときから、ぼくは緊張
しています。 I've been nervous since she arrived here.
Note: in this case, you cannot say "緊張してきました", it sounds funny
because "緊張する" describes your mental condition(nervous).
"緊張してくる" means to become nervous gradually, you use this "くる" when you want to describe someone's condition becoming a certain state gradually.
Example: No.10: あいつのひとりよがりの話を聞いているといらいらしてくる=His self-complacent remarks get on my nerves.
http://dic.yahoo.co.jp/dsearch?p=くる&enc=UTF-8&stype=0&dtype=3
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きみが緊張になってきたのは、学校の試験を休んで言い訳だと思うなら、いい大学に入ると思うな、なぜならさっきの試験はとても大事な試験だったのよ。
If you think that because of being nervous is a good excuse for having missed the exam, don't think you are going to enter in a good university as that exam was really important.
I decided not to worry too much about this sentence, it drives me crazy.