Small-cap stocks were mostly trading higher Wednesday as investors processed another round of earnings reports.

Shares of Minneapolis casual dining entity

Buffalo Wild Wings

(BWLD)

soared 22% to $31.55. The company announced in-line earnings per share of 36 cents, vs. 31 cents a year ago. The EPS figure included a 2-cent charge related to restaurant relocations. The company also guided for a 25% increase in net income for 2008. KeyBanc Capital Markets and Cowen both upgraded the stock to buy and outperform ratings, respectively.

Also rising,

Align Technology

(ALGN) - Get Report

, which offers the Invisalign treatment for crooked teeth, jumped 18% to $12.18. Barrington Research upgraded the Santa Clara, Calif., company to market perform from underperform after a solid earnings beat. The company announced first-quarter profit of $5.3 million, or 7 cents a share, vs. $7 million, or 10 cents a share, a year ago. Analysts were looking for EPS of 3 cents.

Computer systems maker

RadiSys

(RSYS) - Get Report

shot up 21% to $9.83. The Hillsboro, Ore.-based firm announced non-GAAP first-quarter income of $57,000, or breakeven a share, for the first quarter, vs. a profit of $702,000, or 3 cents a share, a year ago. Analysts polled by Thomson Financial were looking for a per-share loss of a penny. The company also forecast non-GAAP second-quarter EPS between 6 cents and 11 cents. The Street is looking for earnings at the low end of that range.

Tronox

(TRX) - Get Report

, which makes titanium dioxide pigment, climbed 22% to $3.53 after narrowing its loss to $200,000, or a 3 cents a share, from $9.4 million, or 22 cents a share, a year ago. Revenue increased to $349.1 million from $339.1 million a year ago.

Among the losers,

Crystallex

( KRY) shares plummeted 46% to 90 cents. Shares stopped trading briefly before the Toronto miner of Venezuelan gold announced that Venezuela's Ministry of the Environment and Natural Resources has denied a request for authorization to carry out exploration activities in the Las Cristinas mining area, where Crystallex hopes to continue development.

Shares of

Savvis

( SVVS), a Town & Country, Mo., provider of information technology services, lost 23% to $14.31. The company suffered a triple downgrade from Lehman Brothers, Jeffries and Kaufman Brothers to hold-equivalent ratings after forecasting 2008 revenue between $840 million and $870 million, below the consensus estimate of $905.5 million.

Finally,

Headwaters

(HW)

, which offers products and services to for construction and energy companies, saw shares fall 19% to $11.62. The company swung to a second-quarter loss of $9.2 million, or 22 cents a share, vs. a profit of $27.2 million, or 59 cents a share, a year ago. Excluding charges, the company lost 11 cents a share. Analysts, who typically exclude one-off items from estimates, were looking for a 4-cent EPS loss on average.

More broadly, the Russell 2000 added 0.7%, and the S&P SmallCap 600 climbed 0.6% to 382.53.