meron po kacng nagpawa sa akin ng kit ,assemble lng kaso,may problema eh, bale gumawa ako bago pcb pero same ung layout nung hindi ko talaga mapagana sa pcb ko tinatry ko sa kasamang pcb ng kit.IC lang at LED at battery lng kinabit ko,pero ang problema gaun din sa unang pcb ang problem,nagiinit ang IC at nag tatrigger agad ung LED.e2 ung orig pcb with parts :
schematic :
halos kahapon hanggang ngaun kong ginagawa yan,talaga di ko man lng mapagana ng hindi nainit IC
sana matulongan nyo ako 
thanks
Medyo more technical tau....
C4 is to ensure n AC ang papasok sa schmitt triggered input CMOS inverter.
R6 and R7 are voltage divider circuit...
R7 is not a bias resistor.For a supply of 5 volt, threshold voltage (Vth) must be approximately has a min. spread voltage approx. equal or near to 1.7volts (V+,min - V-,max). Meaning the negative hysteresis (V-) must be below 1.65volts(approx) and the positive hysteresis (V+) must be above 3.35volts(67%Vcc).
If the V- will not reach below 1.65 volts (33%Vcc), there is no output shift at the CMOS inverter.
After you change the R7 value, you solved the problem....
