lets talk about the specs, the K46CM comes with core i5, GT635M and weights 2kg, while the Zenbook comes with core i5, GT620M and weights 1.46kg. the difference is the graphics card and weight but that is not true that ultrabooks cant handle photoshop (since both are ultrabooks!). the graphics card that the zenbook has is sufficient for photoshopping, as long the graphics card meet the requirements of the photoshop (not sure about autocad though).

UX32VD-R3001H, i5-3317U + Nvidia GT620M + 24GB mSATA SSD + 500GB HDD@RM2999[1.45kg], 4GB, W8
K46CM-WX090H, i5-3317U + Nvidia GT635M@RM2199[2kg], 2GB, 500GB, W8, OD

When you said you "need to use it for autocad and photoshop", do you mean this laptop has to be the primary machine that you use to use some heavy lifting autocad and photoshop work, or this laptop is to open some autocad and photoshop files and do some light amendment / touch up?

Since you are thinking UX32VD, I supposed your budget is around RM3k?

Do you really have to have ultrabook?

The fact:
Autocad and photoshop make use of CPU, quadcore i7 is nice for heavy work. i5 M(obile) is also better than i5 U(LV).
Unless you go into 3D (or some fancy effect), the GPU don't have large impact on autocad and photoshop performance

So the conclusion is like this:
If you don't do 3D (or fancy effect) in autocad or photoshop, UX32VD and K46CM perform more or less the same, since both use the same CPU.
If you do 3D, K46CM is slightly better.
Nevertheless, if you need to do heavy lifting work in autocad and photoshop, preferably look past ultrabook, and get a laptop with i7

If you can live with a 11.6" screen, consider this one Combination of power and mobility 
www.illegear.com
R-11, i5-3210M + Nvidia GT650M@RM2999, 8GB, 500(5400rpm), FreeDOS [CPU options: i5-3210M-i7-3630QM]

yes. there is big difference between GT635M and GT620M. the VRAM doesnt makes difference, as it is not important in graphical processing except if you want a setup of multiple monitors. even it is same spec for both laptops, the weight carried by UX32VD causes the price for the UX32VD is costlier than the K46CM. if i were you with that price, i would look for a powerful netbook, the Illegear R11 (like what sifu nexus said).

If your 3D modelling is small scale (but our definition of "small scale" may differ ), even HD4000 can handle

What I mean:
If you need something powerful and portable, R-11 is good choice.
If your usage of autocad / photoshop is not heavy, UX32VD and K46CM (there is no K36CM ) will perform more or less the same, since both has the same CPU. (So if 1 work for you, the other should be as well; but if 1 suck, the other most likely will suck )
The difference for you then is the weight and price. UX32VD is more expensive (you can find it ~ RM27xx) and lighter. K46CM is near 2kg (without adapter).

With your budget, it's not easy to find 13" with i5.
Asus
S300CA-C1033H, i5-3317U + Intel HD4000 + (1366x768;touch)@RM2399, 4GB, 500GB, W8
Dell
Vostro 3360, i5-3317U + Intel HD4000@RM2249[1.67kg], 4GB, 500GB(5400rpm), W7HB; colors: red/silver/bronze
HP
ProBook 4341s, i5-3210M + AMD HD7570M@RM2699, 4GB, 500GB(5400rpm), W7P, anti-glare
Samsung
NP530U3C, i5-3317U + Intel HD4000 + 24GB mSATA + 500GB HDD@RM2699[1.52kg], 4GB, W8

If you look for 14" ultrabook:
Asus
K46CM-WX090H, i5-3317U + Nvidia GT635M@RM2199[2kg], 2GB, 500GB, W8, OD
Dell
Inspiron 14z, i5-3337U + AMD HD7570M + 32GB SSD + 500GB(5400rpm)@RM2549[1.87kg], 4GB, W8 *no VGA port, OD
Inspiron 14z, i7-3517U + AMD HD7570M + 32GB SSD + 500GB(5400rpm)@RM2749[1.87kg], 8GB, W8 *no VGA port, OD (i7 ULV is still duo core, but faster than i5 ULV)
HP
Envy4-1238TX, i5-3337U + AMD HD8750M@RM2099[Beats][1.75kg], 2GB, 500GB(5400rpm), W8
Lenovo
S400, i5-3317U + Intel HD4000 + 24GB mSATA + 500GB(5400rpm)@RM1999[1.8kg], 4GB, W7HB; AMD HD7450M/W8@RM2199
Toshiba
Satellite U940-1001X, i5-3317U + Nvidia GT630M + 32GB mSATA + 640GB HDD@RM2699[1.7kg], 4GB, W8, backlit keyboard

Prices are RSP, negotiable.

Actually, I love this model precisely because it don't have a stock SSD from HP
Most 14" ultrabook come with a mSATA SSD + SATA HDD combination. Not ideal in term of responsiveness.
This baby just give us the HDD, save cost by omitting the mSATA SSD.

Envy4-1204TX, i5-3337U + AMD HD8750M + 32GB mSATA +500GB(5400rpm)@RM2399[Beats][1.75kg], 4GB, W8
Envy4-1238TX, i5-3337U + AMD HD8750M@RM2099[Beats][1.75kg], 2GB, 500GB(5400rpm), W8

If you look at these two models, the 1238TX save RM300 by omitting the mSATA SSD (more or less). But RM300 can actually get us a 128G SATA SSD  So owner could buy a full SATA SSD, swap with the HDD (keep it as external or trade in), and get a much more responsive, lighter, longer battery performance, cooler running ultrabook