Vidqun
It is my confidence that the prophecy of Daniel deals with other nations, even other 'world powers', namely on the vision concerning the four beasts that arise from the sea. (Chapter 7) But these two visions deal specifically with the Babylonean empire and its demise (chapter 2) and Nebuchadnezzar's punishment period (Chapter 4).
Regarding the use of "olam":
Vine's Expository Dicctionary of Old Testament Words says: " This word has cognates in Ugaritic, Moabite, Phoenician, Aramaic, Arabic, and Akkadian. It appears about 440 times in biblical Hebrew and in all periods."
Therefore, you shouldn't limit the scope of "olam" to the aramaic variation of "elam". They all mean the same across all the linguistic variations, especially the 440 times it appears in Biblical hebrew.
Take, for example, Jeremiah 28:8: " From early times [olam] the prophets who preceded you and me have prophesied war, disaster and plague against many countries and great kingdoms." Clearly, if olam meant "eternity", then the prophets had been prophesying since forever, which is not the case. This an example where olam means "old time" or "long time". Same with Jeremiah 5:15: " Behold, I am bringing against you a nation from afar, O house of Israel, declares the LORD. It is an enduring nation; it is an ancient [olam] nation..." In this case, olam doesn't imply a nation that has existed forever into the past, but simply an "ancient" nation. Also consider the use of olam in Psalm 61:8 " So will I sing praise unto thy name for ever [olam], That I may daily perform my vows." Clearly the intention of olam here is of a "continuous time", but not infinite duration, for the writer of the psalm could only continue to sing praise until he dies.
Jeff A. Berner comments on the Hebrew use of olam: " The word olam is also used for time for the distant past or the distant future as a time that is difficult to know or perceive. This word is frequently translated as eternity or forever but in the English language it is misunderstood to mean a continual span of time that never ends. In the Hebrew mind it is simply what is at or beyond the horizon, a very distant time."
Therefore, you shouldn't be stumbled by the association of the word olam with "kingdom". Both the messianic kingdom and the persian kingdom would last 'into olam', that is, into a presumably long time beyond the horizon. Keep in mind that the Persian empire lasted well over two centuries, more than the normal time horizon of any human being.
Regarding the quality of the materials.
Evidently the gold, silver etc is from a human standpoint - not God's.
i don't agree with you. If materials were irrelevant to God, then he wouldn't require that Gold was used in his temple, nor would he give specifics about what type of materials should be used in his temple.
Eden
Edit: Sorry, I mixed replies to Vidqun with Framegrilled.