Trading see-sawed lower after the closing bell Monday following the regular session's substantial spike. Poor earnings and guidance slammed various companies after hours.

Michigan-based logger

Universal Forest Products

(UFPI) - Get Report

slid 14.5% to $45 after first-quarter earnings, at 20 cents a share, plummeted from last year and widely missed Wall Street's 45-cent estimate, per Thomson Financial.

Fair Isaac

( FIC)

slashed

top- and bottom-line projections for the fiscal second and third quarters, as well as for all of fiscal 2007. The Minneapolis-based credit scorer now expects to make between $1.55 and $1.65 a share in the full year, compared with $2.15 previously. Shares sank $3.97, or 9.8%, to $36.58, in recent extended trading.

Chipmaker

Netlist

(NLST)

plunged 15.4% to $5.05 after chopping a nickel off its profit guidance to range between 2 cents and 3 cents a share. Analysts are seeking 8 cents.

Meanwhile,

BioMarin Pharmaceutical

(BMRN) - Get Report

of Novato, Calif., lost 5.2% to $16.90 after offering $250 million in senior subordinated convertible bonds, with an underwriter's option for $37.5 million more to cover overallotments.

Lawson Software

( LWSN) was also clocked after it offered $200 million in senior convertibles with a $40 million underwriter's option. The St. Paul, Minn., firm recently was sliding 2.9% to $8.70.

A couple of stocks nevertheless managed to ride on the coattails of the regular session's gains. Pasadena, Calif.-based

East West Bancorp

(EWBC) - Get Report

, jumped 6.7% to $38.26 after posting income that shot up 23.6% to 68 cents a share, beating per-share estimates by 8 cents.

Finally, small-cap company

InsWeb

(INSW) - Get Report

, which runs an insurance marketplace Web site, rocketed 54.1% to $5.10 after achieving its first-ever operating profit. The Sacramento, Calif., firm swung to a first-quarter profit of 9 cents a share, reversing a steep year-ago loss.