I have Star Alliance Gold status (*G). Do I have access to the SKL at SIN?
One key exception to standard *G privileges is that the lounge access privilege holds only for
most –
not all – Silver Kris lounges. Specifically, if you’re flying in economy, your *G card won’t allow you to enter the SKL in SIN, KUL and LAX*, because these are not designated *G lounges. (On the other hand, because of special arrangements between SQ, LH and NZ, holders of premium class BPs from LH and NZ are allowed access to the SIN SKL.)
*
Note: The LAX lounge is slated to close soon, to be replaced by a lounge to be shared amongst *A airlines. Expected opening date is in 2006.
The SATS Premier Lounge in SIN’s Terminal 2 is the designated *G lounge. It used to be a dump to which KrisFlyer Elite Golds were also exiled. It was, however, recently refurbished and moved to a location right across the SKL. (Errant *Gs now have a shorter walk to the ‘correct’ lounge.

) Actually, it isn’t a bad lounge. For proof of this, look at the
pictures courtesy of Savage25 and the discussion of the new lounge.
If you really have your heart set on getting access to the SIN SKL and you’re not holding a PPS card or an SQ premium class BP, check
this sticky for the most up-to-date info about FTers who are passing through SIN and are willing to help with access.
Don’t worry about your other privileges as *G. You will still get extra baggage allowance,
priority baggage claim, priority boarding, and business class checkin (this last one except in SIN, where you'll get the good ol' 'preferential treatment' from SQ

, i.e.,
segregation from PPS and SQ premium pax). And you
do get access to some pretty good SKLs, such as the ones at LHR, ICN, and NRT.
How hard is it to redeem miles for First Class and Raffles Class flights?
Given that SQ is generally considered the best (or, on bad days, among the best

) of the *A airlines, you can infer that competition for free flights in the premium classes is fierce. You’ll have an easier time if:
- You’re a KrisFlyer member or, better yet, have PPS status (greater access to SQ award inventory)
- You’re travelling alone (SQ tends to release 1 F award seat at a time, rather than 2)
- You’re OK with Raffles Class rather than First
- You’re not booking for the peak award times (May-June, November-December, the time around Chinese New Year). Note that peak award times are also defined partly by where you are. For example, late December to mid-January is peak time for Australia/NZ flyers.
- You’re flexible with your routing (for example, flying out of MAN rather than LHR)
- You’re flexible with your flight dates
- You book early
- You have the time and patience
to keep calling your airline’s Awards Desk back to check whether an award seat has opened up. SQ has been known to make F award seats available relatively close to the date of departure, so in the past, hope and persistence (and more indefatigable hope) have paid off.Note that it is your FFP’s Awards Desk, not SQ, that you have to deal with. As a member of that FFP, you have access to the award inventory that SQ releases to the FFP, not necessarily the seats that look available in various availability tools.
shortfinals gives a clear explanation of SQ's award inventory policy
here. You may find
this observation by
StarG reassuring when you begin playing the call-back-to-check-availability game.
What’s the best way to get upgraded to Raffles Class from economy?
The short, snippy answer is: use miles from eligible FFPs.

As of August 2005, these FFPs are KrisFlyer and those of selected partners (DL,
LO, LH, OS and NH). Other *A partners are scheduled to be part of the *A-wide upgrade system by 2006. To keep up with the latest developments on this, consult the
thread on How to Upgrade on *A.
But you want the free upgrade, you say, in other words, the 4-letter word dear to FF hearts ("OP-UP")?
Op-ups have been known to happen, but to spend a lot of time strategizing about how to get them seems like a waste, because they are so rare in SQ-Land. This rarity results from SQ’s zealous protection of its premium classes coupled with the SQ yield management software’s amazing ability to avoid overbooking flights.
On the rare occasions that an op-up happens, it will likely be awarded in strict order down a well-defined hierarchy: LPP, then TPP, then QPP, then
KrisFlyer Elite Gold, then other *G, then Elite Silver (although there is anecdotal evidence that Elite Silvers can sometimes trump *G). Honestly, it’s not worth spending the emotional investment wondering whether you'll get an op-up. If you get it, be thankful for your luck that day, and enjoy the unexpected treat

. If you’re a VIP, by the way, the op-up didn't happen because of your ‘luck’.
Look at it this way: if you’ve shelled out the money or miles to sit in, say, Raffles Class, you can at least be comforted by the thought that practically no one sitting in the same cabin got there after having bought only an economy class ticket and nothing more. All of you in that cabin have
earned, in some way or another, the pampering you're about to receive.